I am trying to route a speedrun for the game and was wondering if we use the experimental releases or not. I'd rather not run the game in experimental if the run becomes invalidated for that. This will be my first time speedrunning so I'm not sure if the rule of "Using the newest patch" includes experimentals or not.

I think, newest patch is still about early access versions

All runs are completed in Early Access. None are done in Exp as there can be bugs that can change with a bug fix update.