diff --git a/app/controllers/concerns/turbo_champs_concern.rb b/app/controllers/concerns/turbo_champs_concern.rb
index af5be0438..1a8fc819f 100644
--- a/app/controllers/concerns/turbo_champs_concern.rb
+++ b/app/controllers/concerns/turbo_champs_concern.rb
@@ -4,9 +4,14 @@ module TurboChampsConcern
   private
 
   def champs_to_turbo_update(params, champs)
-    champ_ids = params.keys.map(&:to_i)
+    to_update = if params.values.filter { _1.key?(:with_public_id) }.empty?
+                  champ_ids = params.keys.map(&:to_i)
+                  champs.filter { _1.id.in?(champ_ids) }
+                else
+                  champ_public_ids = params.keys
+                  champs.filter { _1.public_id.in?(champ_public_ids) }
+                end.filter { _1.refresh_after_update? || _1.forked_with_changes? }
 
-    to_update = champs.filter { _1.id.in?(champ_ids) && (_1.refresh_after_update? || _1.forked_with_changes?) }
     to_show, to_hide = champs.filter(&:conditional?)
       .partition(&:visible?)
       .map { champs_to_one_selector(_1 - to_update) }
diff --git a/app/controllers/instructeurs/dossiers_controller.rb b/app/controllers/instructeurs/dossiers_controller.rb
index 51c45ebe6..212a6c8b0 100644
--- a/app/controllers/instructeurs/dossiers_controller.rb
+++ b/app/controllers/instructeurs/dossiers_controller.rb
@@ -273,8 +273,8 @@ module Instructeurs
     end
 
     def update_annotations
-      dossier_with_champs.assign_attributes(champs_private_params)
-      if dossier.champs_private_all.any?(&:changed?)
+      dossier_with_champs.update_champs_attributes(champs_private_attributes_params, :private)
+      if dossier.champs.any?(&:changed_for_autosave?) || dossier.champs_private_all.any?(&:changed_for_autosave?) # TODO remove second condition after one deploy
         dossier.last_champ_private_updated_at = Time.zone.now
       end
 
@@ -282,7 +282,7 @@ module Instructeurs
 
       respond_to do |format|
         format.turbo_stream do
-          @to_show, @to_hide, @to_update = champs_to_turbo_update(champs_private_params.fetch(:champs_private_all_attributes), dossier.champs_private_all)
+          @to_show, @to_hide, @to_update = champs_to_turbo_update(champs_private_attributes_params, dossier.champs.filter(&:private?))
         end
       end
     end
@@ -294,7 +294,12 @@ module Instructeurs
 
     def annotation
       @dossier = dossier_with_champs(pj_template: false)
-      annotation = @dossier.champs_private_all.find(params[:annotation_id])
+      annotation = if params[:with_public_id].present?
+        type_de_champ = @dossier.find_type_de_champ_by_stable_id(params[:annotation_id], :private)
+        @dossier.project_champ(type_de_champ, params[:row_id])
+      else
+        @dossier.champs_private_all.find(params[:annotation_id])
+      end
 
       respond_to do |format|
         format.turbo_stream do
@@ -392,12 +397,36 @@ module Instructeurs
     end
 
     def champs_private_params
-      champs_params = params.require(:dossier).permit(champs_private_attributes: [
-        :id, :value, :primary_value, :secondary_value, :piece_justificative_file, :value_other, :external_id, :numero_allocataire, :code_postal, :code_departement, value: [],
-        champs_attributes: [:id, :_destroy, :value, :primary_value, :secondary_value, :piece_justificative_file, :value_other, :external_id, :numero_allocataire, :code_postal, :code_departement, :feature, value: []]
-      ])
-      champs_params[:champs_private_all_attributes] = champs_params.delete(:champs_private_attributes) || {}
-      champs_params
+      champ_attributes = [
+        :id,
+        :value,
+        :value_other,
+        :external_id,
+        :primary_value,
+        :secondary_value,
+        :numero_allocataire,
+        :code_postal,
+        :identifiant,
+        :numero_fiscal,
+        :reference_avis,
+        :ine,
+        :piece_justificative_file,
+        :code_departement,
+        :accreditation_number,
+        :accreditation_birthdate,
+        :feature,
+        :with_public_id,
+        value: []
+      ]
+      # Strong attributes do not support records (indexed hash); they only support hashes with
+      # static keys. We create a static hash based on the available keys.
+      public_ids = params.dig(:dossier, :champs_private_attributes)&.keys || []
+      champs_private_attributes = public_ids.map { [_1, champ_attributes] }.to_h
+      params.require(:dossier).permit(champs_private_attributes:)
+    end
+
+    def champs_private_attributes_params
+      champs_private_params.fetch(:champs_private_attributes)
     end
 
     def mark_demande_as_read
diff --git a/app/controllers/users/dossiers_controller.rb b/app/controllers/users/dossiers_controller.rb
index 00234d794..06dd6d742 100644
--- a/app/controllers/users/dossiers_controller.rb
+++ b/app/controllers/users/dossiers_controller.rb
@@ -284,7 +284,7 @@ module Users
           end
 
           format.turbo_stream do
-            @to_show, @to_hide, @to_update = champs_to_turbo_update(champs_public_params.fetch(:champs_public_all_attributes), dossier.champs_public_all)
+            @to_show, @to_hide, @to_update = champs_to_turbo_update(champs_public_attributes_params, dossier.champs.filter(&:public?))
             render :update, layout: false
           end
         end
@@ -298,7 +298,7 @@ module Users
 
       respond_to do |format|
         format.turbo_stream do
-          @to_show, @to_hide, @to_update = champs_to_turbo_update(champs_public_params.fetch(:champs_public_all_attributes), dossier.champs_public_all)
+          @to_show, @to_hide, @to_update = champs_to_turbo_update(champs_public_attributes_params, dossier.champs.filter(&:public?))
           render :update, layout: false
         end
       end
@@ -310,7 +310,12 @@ module Users
 
     def champ
       @dossier = dossier_with_champs(pj_template: false)
-      champ = @dossier.champs_public_all.find(params[:champ_id])
+      champ = if params[:with_public_id].present?
+        type_de_champ = @dossier.find_type_de_champ_by_stable_id(params[:champ_id], :public)
+        @dossier.project_champ(type_de_champ, params[:row_id])
+      else
+        @dossier.champs_public_all.find(params[:champ_id])
+      end
 
       respond_to do |format|
         format.turbo_stream do
@@ -478,7 +483,7 @@ module Users
     end
 
     def champs_public_params
-      champs_params = params.require(:dossier).permit(champs_public_attributes: [
+      champ_attributes = [
         :id,
         :value,
         :value_other,
@@ -496,10 +501,18 @@ module Users
         :accreditation_number,
         :accreditation_birthdate,
         :feature,
+        :with_public_id,
         value: []
-      ])
-      champs_params[:champs_public_all_attributes] = champs_params.delete(:champs_public_attributes) || {}
-      champs_params
+      ]
+      # Strong attributes do not support records (indexed hash); they only support hashes with
+      # static keys. We create a static hash based on the available keys.
+      public_ids = params.dig(:dossier, :champs_public_attributes)&.keys || []
+      champs_public_attributes = public_ids.map { [_1, champ_attributes] }.to_h
+      params.require(:dossier).permit(champs_public_attributes:)
+    end
+
+    def champs_public_attributes_params
+      champs_public_params.fetch(:champs_public_attributes)
     end
 
     def dossier_scope
@@ -532,8 +545,8 @@ module Users
     end
 
     def update_dossier_and_compute_errors
-      @dossier.assign_attributes(champs_public_params)
-      if @dossier.champs_public_all.any?(&:changed_for_autosave?)
+      @dossier.update_champs_attributes(champs_public_attributes_params, :public)
+      if @dossier.champs.any?(&:changed_for_autosave?) || @dossier.champs_public_all.any?(&:changed_for_autosave?) # TODO remove second condition after one deploy
         @dossier.last_champ_updated_at = Time.zone.now
       end
 
diff --git a/app/models/champ.rb b/app/models/champ.rb
index b3672d9f0..fc7ee4aa1 100644
--- a/app/models/champ.rb
+++ b/app/models/champ.rb
@@ -2,6 +2,9 @@ class Champ < ApplicationRecord
   include ChampConditionalConcern
   include ChampsValidateConcern
 
+  # TODO: remove after one deploy
+  attr_writer :with_public_id
+
   belongs_to :dossier, inverse_of: false, touch: true, optional: false
   belongs_to :type_de_champ, inverse_of: :champ, optional: false
   belongs_to :parent, class_name: 'Champ', optional: true
diff --git a/spec/controllers/instructeurs/dossiers_controller_spec.rb b/spec/controllers/instructeurs/dossiers_controller_spec.rb
index 108c675ba..f4f065948 100644
--- a/spec/controllers/instructeurs/dossiers_controller_spec.rb
+++ b/spec/controllers/instructeurs/dossiers_controller_spec.rb
@@ -1005,25 +1005,25 @@ describe Instructeurs::DossiersController, type: :controller do
             dossier_id: dossier.id,
             dossier: {
               champs_private_attributes: {
-                '0': {
-                  id: champ_multiple_drop_down_list.id,
+                champ_multiple_drop_down_list.public_id => {
+                  with_public_id: true,
                   value: ['', 'val1', 'val2']
                 },
-                '1': {
-                  id: champ_datetime.id,
+                champ_datetime.public_id => {
+                  with_public_id: true,
                   value: '2019-12-21T13:17'
                 },
-                '2': {
-                  id: champ_linked_drop_down_list.id,
+                champ_linked_drop_down_list.public_id => {
+                  with_public_id: true,
                   primary_value: 'primary',
                   secondary_value: 'secondary'
                 },
-                '3': {
-                  id: champ_repetition.champs.first.id,
+                champ_repetition.champs.first.public_id => {
+                  with_public_id: true,
                   value: 'text'
                 },
-                '4': {
-                  id: champ_drop_down_list.id,
+                champ_drop_down_list.public_id => {
+                  with_public_id: true,
                   value: '__other__',
                   value_other: 'other value'
                 }
@@ -1074,12 +1074,11 @@ describe Instructeurs::DossiersController, type: :controller do
       end
     end
 
-    context 'with invalid champs_public (DecimalNumberChamp)' do
-      let(:types_de_champ_public) do
-        [
-          { type: :decimal_number }
-        ]
-      end
+    after do
+      Timecop.return
+    end
+
+    context "with new values for champs_private (legacy)" do
       let(:params) do
         {
           procedure_id: procedure.id,
@@ -1095,9 +1094,63 @@ describe Instructeurs::DossiersController, type: :controller do
         }
       end
 
+      it 'update champs_private' do
+        patch :update_annotations, params: params, format: :turbo_stream
+        champ_datetime.reload
+        expect(champ_datetime.value).to eq(Time.zone.parse('2024-03-30T07:03:00').iso8601)
+      end
+    end
+
+    context "without new values for champs_private" do
+      let(:params) do
+        {
+          procedure_id: procedure.id,
+          dossier_id: dossier.id,
+          dossier: {
+            champs_private_attributes: {},
+            champs_public_attributes: {
+              champ_multiple_drop_down_list.public_id => {
+                with_public_id: true,
+                value: ['', 'val1', 'val2']
+              }
+            }
+          }
+        }
+      end
+
+      it {
+        expect(dossier.reload.last_champ_private_updated_at).to eq(nil)
+        expect(response).to have_http_status(200)
+      }
+    end
+
+    context "with invalid champs_public (DecimalNumberChamp)" do
+      let(:types_de_champ_public) do
+        [
+          { type: :decimal_number }
+        ]
+      end
+
+      let(:champ_decimal_number) { dossier.champs_public.first }
+
+      let(:params) do
+        {
+          procedure_id: procedure.id,
+          dossier_id: dossier.id,
+          dossier: {
+            champs_private_attributes: {
+              champ_datetime.public_id => {
+                with_public_id: true,
+                value: '2024-03-30T07:03'
+              }
+            }
+          }
+        }
+      end
+
       it 'update champs_private' do
         too_long_float = '3.1415'
-        dossier.champs_public.first.update_column(:value, too_long_float)
+        champ_decimal_number.update_column(:value, too_long_float)
         patch :update_annotations, params: params, format: :turbo_stream
         champ_datetime.reload
         expect(champ_datetime.value).to eq(Time.zone.parse('2024-03-30T07:03:00').iso8601)
diff --git a/spec/controllers/users/dossiers_controller_spec.rb b/spec/controllers/users/dossiers_controller_spec.rb
index 5253ba54c..ad99422a4 100644
--- a/spec/controllers/users/dossiers_controller_spec.rb
+++ b/spec/controllers/users/dossiers_controller_spec.rb
@@ -674,12 +674,12 @@ describe Users::DossiersController, type: :controller do
         dossier: {
           groupe_instructeur_id: dossier.groupe_instructeur_id,
           champs_public_attributes: {
-            first_champ.id => {
-              id: first_champ.id,
+            first_champ.public_id => {
+              with_public_id: true,
               value: value
             },
-            piece_justificative_champ.id => {
-              id: piece_justificative_champ.id,
+            piece_justificative_champ.public_id => {
+              with_public_id: true,
               piece_justificative_file: file
             }
           }
@@ -719,7 +719,7 @@ describe Users::DossiersController, type: :controller do
           {
             id: dossier.id,
             dossier: {
-              champs_public_attributes: { first_champ.id => { id: first_champ.id } }
+              champs_public_attributes: { first_champ.public_id => { with_public_id: true } }
             }
           }
         end
@@ -747,7 +747,7 @@ describe Users::DossiersController, type: :controller do
         {
           id: dossier.id,
           dossier: {
-            champs_public_attributes: { first_champ.id => { id: first_champ.id, value: value } }
+            champs_public_attributes: { first_champ.public_id => { with_public_id: true, value: value } }
           }
         }
       end
@@ -790,12 +790,12 @@ describe Users::DossiersController, type: :controller do
         dossier: {
           groupe_instructeur_id: dossier.groupe_instructeur_id,
           champs_public_attributes: {
-            first_champ.id => {
-              id: first_champ.id,
+            first_champ.public_id => {
+              with_public_id: true,
               value: value
             },
-            piece_justificative_champ.id => {
-              id: piece_justificative_champ.id,
+            piece_justificative_champ.public_id => {
+              with_public_id: true,
               piece_justificative_file: file
             }
           }
@@ -855,8 +855,8 @@ describe Users::DossiersController, type: :controller do
             id: dossier.id,
             dossier: {
               champs_public_attributes: {
-                piece_justificative_champ.id => {
-                  id: piece_justificative_champ.id,
+                piece_justificative_champ.public_id => {
+                  with_public_id: true,
                   piece_justificative_file: file
                 }
               }
@@ -951,8 +951,8 @@ describe Users::DossiersController, type: :controller do
           id: dossier.id,
           dossier: {
             champs_public_attributes: {
-              first_champ.id => {
-                id: first_champ.id,
+              first_champ.public_id => {
+                with_public_id: true,
                 value: value
               }
             }