1.0 players do not get a free month unless they repurchase the game, from my understanding. They do, however, get the game free and fourteen days for free (September 9th).

I'm sure a week or two after launch they'll at least have something up by then for 1.0 players that wish to continue their subscription but weren't able to put in their information before. That's when the opportunity will open up as well for the rest of the players.

(Just guessing.)