Out of curiosity what is the gear level on it? All I could find was 845 for mythic.
I added up every quest last night and it was just shy 8k not sure how you got 2k more (this was with zero artifact power).
Anywho, 9950 AP in 6 hours. Let's say a competent premade dungeon group of mythic raiders at ~865 ilvl can do 1 dungeon every ~6 minutes. Some will be shorter, some will be longer, mainly because of RP, (Halls of Valor says hi) I think a fairly average amount of AP to get per dungeon is 265. That assumes 3 Jewels of Victory, which may be a tad on the high side, but since you're killing so many mobs you have a decent chance of getting some Brief Histories of the Aeons, which are another 100, and sometimes you get rare spawns and chests in the dungeon that give an extra Jewel of Victory.