UE5 Blueprint values reset on editor startup

Development Programming & Scripting
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1

Hey. We are using mostly BPs to implement game logic, and after transition from UE4.27 to UE5.1 we started having some random value resets on some of the BPs.
For example, one of the BPs is BP_A, it loses “Replicates” checkbox value. I set it to true → save → close project → open project → it is false.
I tried to open project and reload the asset to see what happens, and it crashes.
For instance let’s say BP_C inherits from BP_B, which inherits from BP_A, and BP_Z is something that references them.
I opened Rider to investigate Unreal logs, and it has some messages.
The reload first error is this:

Error LogBlueprint [AssetLog] *PathToProject*\BP_A.uasset: [Compiler] Can't connect pins A Class and Return Value : BP A Class Reference is not compatible with BP A Class Reference.

And after that:

Ensure condition failed: !SkeletonToRelink->GetSuperClass()->HasAnyClassFlags(CLASS_NewerVersionExists)...
[Callstack] 0x00007ffc0cd796c5 UnrealEditor-Kismet.dll!FBlueprintCompilationManagerImpl::FlushCompilationQueueImpl()...

Later:

Error LogBlueprint [AssetLog] *PathToProject*\BP_Z.uasset: [Compiler] Can't connect pins As BP C and Target : BP C Object Reference is not compatible with BP A Object Reference.

Later:

Warning LogBlueprint [AssetLog] *PathToProject*\BP_Z.uasset: [Compiler] 'BP C' does not inherit from 'BP B' ( Cast To BP_C would always fail).

Later:

Error LogBlueprint [AssetLog] *PathToProject*\BP_Z.uasset: [Compiler] COMPILER ERROR: failed building connection with 'BP C Object Reference is not compatible with BP A Object Reference.' at Get (a copy) generated from expanding For Each Loop

Does anyone have any idea what is happening? It only started with the transition to UE5.1, and never happened before.
Similar happens to some other assets as well, which randomly start losing some values set, but this one I am talking about in this post only affects the Replicates checkbox, which is Unreal built-in, not our project-specific, so there must be something wrong going on. Perhaps we are doing something incorrectly with the asset management?

2

I have absolutely no idea why your project won’t let you change your settings/variables, but would it work to cheese it by just setting all the incorrect values to their correct ones on the begin plays of the affected actors?

3

This would solve this problem only, but we have the same happening to some other variables and other blueprints. If we scale this to 100 variables, setting all of them only inside BP is a no-go.
We need to find what is the root cause and fix the problem, cheesing doesn’t help much, unfortunately.