How does Wintergrasp Queue Work?

I queued for WG at 14 mins 58 seconds, and spectated 2 arena games my friends were playing. They logged on their alts and queued after those games, and they both got the queue but I didn't despite me being queued at least 5 minutes longer than they were. I always thought it was first come first serve? This is the third WG in a row I've missed today, and every time I've queued at least 12 minutes before the game starts. It gets pretty old pretty fast to wait around for 25 minutes before a game and not get queues despite spamming the NPC and queuing the second it becomes available.

Just do nothing with changing your instances during last 15 mins before WG. Go grab some drinks, smoke or whatetever, just do not queue any aditional BG's/SoloQ's/spectates, should be okay