Guild Wars 2 forum user Linfang posted a blurb about veteran character slots yesterday that’s probably worth a read if you’re a fan of ArenaNet’s fantasy MMO. The info comes from the GW2 FAQ and subreddit, and it states that if you registered your core game prior to January 23rd, 2015, and you register a pre-purchase Heart of Thorns serial before the expansion releases, you’ll get a free character slot.
If your account was made eligible by July 9th, your free slot should have applied yesterday (July 10th).
Source: Forums; thanks Pretty Pixie!