Question about transfering ip address range to another ASN owned by same company

Our company has two IP address ranges we’d like to transfer from a company we bought
and absorbed, which has the ranges attached to a different ASN.

My question is, other than having to update the config for the current peer,
how much down the road interruption would I be looking at? Any possibility of a
major outage as the ranges transfer from the one ASN to ours?

Thank you,