Caffeine supplementation during a meet

This is a topic that i couldn’t really find much about on the internet (surprisingly) because we know how useful caffeine can be as a performance enhancer

But when do you guys (assuming that you take it) use caffeine during your meets? And do we really know when is the best time to take it? Idk if that’s nuanced or not, i remember reading about 40 minutes before lifting is alright? Thank you.