Validators can immediately unstake if they're removed from a set

[kayabaNerve]

A validator can deallocate enough stake they'll no longer be selected for participation, and then once no longer present, deallocate the rest of their stake. This avoids the deallocation time delay for part of their stake.

Since a validator can't deallocate to less than a key share of stake, this is only possible if the set has the maximum amount of validators (causing only the best to be selected, where one can deallocate enough to not be the best but still have a key share).