I queued for Cyrodiil over an hour ago, and since I was expecting it to take about an hour (according to what the queue said), I went to Imperial City to do a daily there for the event ticket, did my crafting dailies, did my daily endeavors, did my daily three PvE Tribute matches, went to Craglorn to run around farming resource materials, and ended up at position 23 in the queue. (I don't remember my starting position, but I think it was 50+, like maybe 59 or 57.)
So I decided to do the Spellscar quest while I waited. I ran around killing spellfiends for the elemental energies, then entered inside and worked on the quest, checking the queue from time to time. It was stuck at position 23-- did not budge, not even by 1. The estimated wait time changed, from 11 minutes to 49 minutes to 34 minutes, etc., but my position in the queue never varied.
I have other things to do today IRL, so I decided to just abandon the queue and try again later this evening. I selected the option to abandon the queue, but received the message that I was not queued for that campaign. The queue display changed from a position number (23) to the "leaving queue" message, but the message would never go away and the option to leave the queue would never go away-- it was just frozen on "leaving queue."
I appreciate that there are other campaigns besides my hone campaign, which I can queue into to grab my other 2 event tickets. This post isn't to complain about not being able to get into my home campaign. It is yo let you know that there is something broken about the queue. I've seen this during other Mayhem events, where an abnormally long queue time would show gradual decreases in my queue position as I edged closer to the head of the queue, but then after having been in the queue for over half an hour it gets stuck at some position and will not budge from there. No amount of patient waiting will show any progress, and trying to keave the queue just gives you the message that, hey, you aren't even queued for that campaign, then you're stuck with a "leaving queue" message that will not go away. Your only option for making that message go away so you can try to rejoin the queue seems to be to log out of the game entirely.
I've fought mudcrabs more fearsome than me!