Bulk Update Bill-To Address for Customer Account Site

Summary: Account Receivables - Our business user is trying to end-date the existing bill to address for a customer only for selective accounts - site level.
And create a new bill to site and enable that as a 'Primary' bill-to site.

Based on the above requirement what is the best process to follow.

As per our check same bill-to is used for most of the accounts and in case we end-date and change bill-to there would be any impacts.

And also if we modify the primary bill to site flag and leave the old bill-to as is, without end-dating would that cause an impact.