Beta ended early

When I left at 8am it said 20 hours remaining till beta ends. At this point there should be 10 hours remaining or so. Why did it end earlier than it should ?

The timer was a bit off. The beta also started several hours before the timer said it would start. I believe the designated allotted time was still reached.
I missed a few hours at the start myself because I planned to install it in the hours leading up to launch, but then saw that streams of the beta were live.