Please note this affects all savegames from before 1.54.133741. The example below relates to the Campaign.
Since 1.54 I have not been able to start the Breaking Even mission from the Gori outpost. I can start the briefing without any problem, walk around the base and rearm but the game sends me back towards the campaign menu once the screen fades out after I go to the 'regroup' point.
First error message displayed in the campaign menu after it crashes:
"Cannot load the saved game. Incompatible versions"
Second error message:
'Unable to load C:\Users\XXX\Documents\Arma 3\Saved\Missions_F_EPB\Campaign\autosave.Arma3Save'
The same error occurs with or without mods.