Expansion extra character slot question
From the FAQ:
Free character slot
If you registered your core Guild Wars 2 game before January 23, 2015 and register a pre-purchase serial code for Heart of Thorns any time before the expansion is released, you’ll receive a free character slot! Once you apply a pre-purchase serial code, you’ll be eligible for the slot regardless of where you bought the core game.
If the serial code you used to register the core game came from a retail vendor (rather than buy.guildwars2.com or in-game) and was applied to your account between January 23, 2015 and June 16, 2015, you’ll also be eligible for a free character slot if you apply a Heart of Thorns pre-purchase serial code before the expansion release.
All accounts that become eligible by July 9 will have their free character slot applied by July 10. Eligible accounts that are upgraded with a pre-purchase serial code after July 10 will receive their slots on a weekly basis after that.
https://help.guildwars2.com/entries/94582027-Heart-of-Thorns-Pre-Purchase-FAQ/#Additional