Hi @lalajee
Are you referring to TPM startup pin on the device?
If yes, that is specific to device and it is stored in TPM chip present locally on the device. So your during migration you don't have to worry about TPM pin. Just make sure the policy are replicated and there will not be any need for reencryption unless there is a bitlocker policy change
Regards
Aravinth
If this is helpful,kindly accept as answer