I have been in at least 2 pvp matches where 1 ranger changes pets and the 1st pet is still there attacking and doing damage while the other pet is also using its skills. The last match a bristleback was doing its ranged attack while the smokescale was blinding me at the same time. there was only 1 ranger and 1 enemy near me.
I dont know if others have seen this bug but it has happened to me more than once.