I thought last year the codes for May were released in mid February. I know I used one, but am not real sure when they came out. I know the Chase Visa ones came out first, then the ones for AP holders, then Florida residents, then general public codes. I know the room only rates came out first then the pkg codes, because I booked a room only first then changed it a few days later to a pkg.
I'm planning on going May 3rd-11th this year, but am not in any hurry to book and won't be concerned until late Feb. I figure the fewer rooms they have booked, the better our chances for codes are.