High Elin pq - Leader Dc 5 times in a row (diffrent leaders)

Description of the bug: (optional screenshot/video): Ellin pq - Leader Dc 5 times in a row every time we get to the row the leader of the party dc, we try to change leaders every time, but the same happen over and over again.
What is supposed to happen?:not dcd.
Where did you find and/or notice this bug?:ellin pq boss stage.
A step-by-step guide to re-producing this bug (optional):
Extra information (optional): 5 diffrent leaders were dcd, and had never dc for no reason before... so i think this is a bug. it's always only the leader who dc.

 

Does it happen the moment the boss is spawned or when a leader enters the map?
the time of the dc is changed and not casual, but most of time 4/5 was in while boss fighting or sec befoe enter boss.

Also, are there any error when client disconnects?
no error after dc. you can login easly.

 

also i tried the pq agian 4 hours later and it was fine. no dc to anyone.
so idk y every leader dc at 10pm

 

now dc agian for the leaders...