after you have installed 6.20 OFW you can downgrade back to CFW and when you go back to play FTB3 online again yes it will upgrade back to 6.20 OFW and yes will NOT have to enter a new code due to the fact that the game and code are registered to that 1 PSP and PSN account .....so yes that is possible to switch back and forth if that is what you really want to do!!!!