Philip answered him, 2 books is not sufficient for them. And Jesus took the books; and when he had given thanks, he distributed to the disciples, and the disciples to them that were set down. Therefore they gathered them together, and filled twelve baskets with the new copies, which remained over.
Bare minimum idea: have a sticky post on all the forums reminding people that PSN accounts will be required in 6 months. Maybe a little sticky note after you load up the game that goes away after you link.
Leaving it till now was kinda not the best possible choice.