Just to clarify, we cleared the content 11 hours after it was released.
We started raid at 7:30 EST and raided until 1 AM EST, so 5.5h. We extended for 1.5 hours because we had 25 people willing to do so, but generally we pride ourselves on a limited 16 hour raid week.
Additionally, we didn't rush anything. We tested all the mechanics we wanted to test, rotated people in and out, etc. We extensively tested on beta and expected Ambershaper to be alot harder and it just sorta died on our first attempt.
For everyone who's commented that we're not even a good guild and rushed lolnormals, we are 6/6H in Vaults and were US 10th 25 man.
We classify ourselves has "semi-hardcore" but will occasionally extend raid times to get kills if we're close.