When to move down?

[Pancho]

I was wondering, if i need 300BB as a starting bankroll for a limit. let's say 1200 for 2/4 limit.

How low has my roll to get, for me to move down to 1/2??

cause theoretically i already don't have the rquired roll, if i lose a 100.

Maybe it's a standard question, but couldn't find it so pls some help on it.

Thx

[plexiq]

I think the "default" advice is to move down when you approach the 300BB-level of the limit below your current one. (Or earlier, if you realize you cant beat the limit, of course...)