Project crashing when opening any Blueprint

I’m becoming increasingly frustrated with this issue. It’s appeared twice now, and it’s pretty much impeded progress both times. The issue is that sometimes, if I close a project and come back to it later, upon reloading the project, opening any Blueprint (or any map) will cause the whole Editor to crash and show this error message:

Assertion failed: bCustomPropertyListForPostConstructionInitialized [File:D:\Build++UE4+Release-4.17+Compile\Sync\Engine\Source\Runtime\Engine\Private\BlueprintGeneratedClass.cpp] [Line: 563]

I have no clue why this is happening. I save every file I’m working on every time to make sure that issues like this don’t happen. The first time, I managed to fix the issue by methodically removing files from the Content folder until it stopped crashing, then found that many Blueprint variables had somehow become corrupted. I spent hours adding references back, inserting links between nodes that had somehow disappeared and ticking checkboxes on some boolean nodes that had become unticked. I also did a thorough sweep of the project to make sure there were no circular references and combed through every file to make sure there was nothing that felt off.

I checked online for a definitive solution or prevention method, and nothing that was suggested worked. I tried backing up then deleting the Intermediate, Build and Saved folders and this didn’t solve the issue.

It’s just happened again. If anyone has a solution to this issue, I’d very much appreciate it because it’s a complete roadblock on my progress.