How to mass close/open payables from one ledger to the next?

Summary:

We are considering changing our Fiscal Year to the Calendar Year and would like to know how to mass close/open payables from one ledger to the next.

Content (please ensure you mask any confidential information):

We are looking to ensure the Payables get "re-loaded" into AP but under a different/new BU.

Example: we have 1k invoices in AP, 200 need to be paid out and 800 need to remain open, those 800 would need to be cutover to the new BU but remain open in AP so they can be paid under the new BU

This also means payables that are still "in flight" - waiting approval or have some issue and/or any payments that have not been cashed/cleared the bank.