Corrupt Blueprint but no so much? (Haunted?)

Hello!

I was wondering if anyone has ran into an issue like this, project runs fine on 5.3.2, but after upgrading to 5.4, if I don’t open one specific blueprint (BP_ButtonBase) which basically all of our UI inherits from, then every level that references it, crashes the engine.

If I open the bp,compile it and save it, then everything works fine.

Is this a corrupt bp? I have tried the upgrade process twice, and it always ends up in the same result and the same bp with the problem.

Here’s the call stack