PF + OAB in migration from 2007 to 2013

I am writing up a plan to migrate from Exchange 2007, to 2013. When I stand up my first Exchange 2013 server, I believe an arbitration mailbox with "OrganizationCapabilityOABGen" will be created.

I will migrate user mailboxes and Public Folders to the new server and will delete PFs from my E2007 server. Since all of my current OABs are setup for PF and web distribution, I will also disabled PF distribution.

I have two questions:
1. Once I've disabled PF distribution of my OABs, will I be able to delete my PF database?
2. Do I need to do anything else to ensure that OAB generation is swung to Exchange 2013 (before decommissioning E2007)?

Thanks.