I have been in my current band just over a year and we’re about to move onto drummer number 3 .
We have a gig next Friday, which the outgoing guy said he’d cover, although his departure could still be regarded as without warning (I actually doubt whether many folk who quit give a lot of notice). Would I use a previous member of a band again once they’d departed? Probably, provided they were good at the job and not absolute jerks.