Hopefully I don't get dogpiled for this but I'll explain why the AV queues suck for Horde, from an Alliance perspective. TL;DL: map is dogshit so Alliance stopped queueing. 99%/1% Horde win rate. From my my personal experience grinding to Rank 11 I'd say WSG/AB maps are balanced, roughly 50% win rate when it's pug vs pug. AV on the other hand is extremely imbalanced. Would you like to know more?
Basically they were lazy and gave us the 1.12 map that is not balanced at all, it was in the game for like a month before TBC came out and they added reinforcements. This was back in 2005 when we were all retards and didn't know how to play so the flaws weren't so exposed. They eventually moved the Horde cave back south later in TBC when people figured out how broken it was.
The first forward GY for each team are SHGY (Alliance) and IBGY (Horde). This version of the map has the Horde cave right next to IBGY where if they die they rez at the cave 20 at a time, 20 seconds away. If Alliance dies at their forward GY (SHGY) they get sent back to SPGY where they rez 10 at a time, 50 seconds away. This compounds into like a 200vs40 situation where Alliance has to severely outplay the Horde to have a chance.
Horde can just ignore IBGY and just has to zerg SHGY and soft cap it, and all Alliance get sent to the north of the map and choked off from going south for the rest of the game. Then Horde can retake IBGY at their leisure due to cave respawns, rezzing 20 at a time and whittling down whatever Alliance offense is still south.
I could go on about other things but that's the basics of it. Alliance does queue on AV weekends and actually win once in a while if we're facing a soup helmet Horde team, so yeah queues are a little bit shorter then. Overall I would expect them to get longer though because the only Alliance doing AV now are 51-59 alts and rep farmers.
A simple fix that might bring Alliance back is if they made it so you don't rez in the cave until there's no other GY's left. They won't of course, but here's some light reading on the subject if anyone is interested:
AV Cave Rez situation