AWS Provisioned Concurrency and version?

Ok, so provisionedConcurrency might be the best idea since sliced bread but I do have a pondering about how to handle the versions and what is actually being kept “warm”…

The provisionedConcurrency setting in Serverless works fine and sets the correct value, e.g. “5” but the version set is always version 1 it seems.
It’s a bit tricky as you can’t set the provisionedConcurrency on version “LATEST” (which would be ideal) so question is, can I use provisionedConcurrency from Serverless or will that only keep version 1 “warm” while the used “LATEST” is cold?