I think you're right. I thought I remembered seeing somewhere that it was either November 1 or 1st competition whichever came first, but I think I'm wrong. It doesn't matter what level you started on, but you can't compete at Worlds. This is last year but here's an excerpt from the rule:
All athletes participating on a team at The 2014 Worlds must be a registered member of that team’s gym during the
2013-2014 competition season. Any athlete that has competed on the floor with a team in any level from a gym
(Primary Gym), during the Worlds competition season (November 1, 2013 – May 1, 2014), will have to have a USASF
Gym Release Waiver signed by the owner of that gym (Primary Gym) before that athlete is eligible to compete with
another gym (Secondary Gym) at The 2014 Cheerleading Worlds.