I assume i'd have to buy time cards to do it, as i'm already subbed for 180 days and it won't let me add anymore until it finishes in Feb/March. But even if I did get time cards, would it actually let me add them ontop of the 180 days I already have?

Super excited for the Behemoth mount, so it'll be kinda disappointing if you can't get it just because of the crappy subscription system.