How does queue prioritization for Cities work?

[Cyrinael]

Yesterday we queued as 5-man party for AD like 7 minutes before the deadline and did not receive a pop for an instance, leading me to wonder how the Queue Prioritization works. As far as I can tell there were more than enough players waiting outside (like 40-50) for both factions, most of which would have possible queued (and not stand there afk). As I have often queued 7-9 minutes before the deadline with a 12/18/24 warband and received an instant pop, I suspect this has something to do with (i) queuing as 5 man, thus needing a single player to fill our party and/or (ii) having not enough archetypes (healers/tanks/dds) even though enough players queued (for example there are only 3 healers and 18 DDs and 8 tanks queued) - nevertheless I have already seen instances with only 2 or 3 healers so this should not be the case...
There were even some players saying afterwards they were queued for 10 or 25 minutes and did not get a pop, so more players were clearly affected by this...

Also how does queueing with a 6 man as party or as warband does affect prioritization? From what I can tell, if you queue as group you will get in as replacement into an already open instance, while as warband you will get into a new instance ?!

Furthermore, are larger warbands prioritized over smaller ones? For example, a 18 and a 24 warband queue simultaneously; which will get the next instance? Or is it all first come, first served?

[Noslock]

Seems random sometimes. We usually queue as 24 and sometimes people from guild in another wb who queue later than us gets pop before us.

[Alfa1986]

Yesterday we, as a group 2/2/2, were queue on AD, and hit with one famous organized bomb warband. taking into account the fact that on our side one group was completely without healers, naturally we practically could not do anything and lost all three stages and were completely trampled, although if the last team had healers then .... it seems to me alone that the mismatch system works somehow strange?)