From the full announcement on the EQII forums:
But, we don't really want to force those decisions on returning players. It's not a fun experience to come back to something that seemed exciting (F2P) and then get hit with a bill as soon as you arrive, just for the privilege of using your current characters.
So here's what we're going to do.
*Every* character that was created before 12/06/2011 at 12:01 a.m. will be grandfathered in without race or class restriction. This means that regardless of your membership level, you will be able to play any character created before 12/6 without paying for race- or class-pack unlocks.
For any player that previously subscribed to EQII Live servers, or as a Gold or Platinum member on EQ2X, we will also refund all the class/race pack purchases made after 12/06/2011 at 12:01 am and before the time of this posting (12/08/2011, 4:30pm) so that no one loses any SC due to this change.