Are Vista printers managed exclusively from iManager 2.7?

I have my Manager/Broker server patched to SP7. I understand I need to update the RBS collection to support iManager 2.7. After updating RBS, can 2.6 still be used to manage previous (non-Vista) printers, or at that point am I committed to using 2.7 for all iPrint management?

Asking because of mixed 2.6/2.7 tree scenario mentioned here: