Well we had some good luck yesterday ^^ a Blizzard bug to our favour? NEVAH! but seriously... we were in AQ20 trying the second boss for the first time we wiped 2 times and on the third attempt we were going great, 6th wave and only 2 dead (me and another mage >< ) then all of a sudden after the 6th wave died... everything stopped... we were removed from combat, the elites were standing in their usual spot awaiting the next wave but nothing came... so we ressed the dead, healed up and re buffed then had a go at pulling one of the sets of mobs which SHOULD have come anyway.
We wiped the floor with the mobs pull and the boss spawned right after it as if nothing had happened

now im not sure if that was a bug but im pretty sure the event is not ment to stop and allow everyone to rest up? isnt it just ment to be on going until the boss is down?