I just wanted to clarify something with the moderators. For the sake of competition, is it allowed to use external tools to role back the game version to a previous version? Some changes (such as the Lithuanian food bonus) made it impossible to beat times in some categories so I wanted to make sure we could go back in order to try and lower times. If this is allowed, is there any limit to how far we can go back or can we choose any version we like so long as we still aren't using glitches or exploits specific to certain versions?

Yes, you can use any version with rollback by downloading from steam depots. Big limits are indeed lithuanians for fast feudal and market for other age ups.

Let me the mod confirm this too

The answer is yes, you could even roll back to the release version of DE way back in 2019 if you'd like.

This applies to all categories, including campaigns.