Okay this is the problem:

Now, the normal contests begin in 22:35 (UTC +8), many chinese users like me have to stay up to 11:30.

I don't wanna stay up, so I do the contests when they are before 21:30. But half of them are kind weird so I got negative delta.

When I stay up, I am too tired to do the problems.

So I always cannot get my rating up to Specialist, even through I can get 1500 perf in Atcoder Beginner Contest and 1200 perf in Atcoder Regular Contest.

At the end I wish the contest holders:

plz, make more contests that do not begins at 22:35. (Also for some american friends who can't get up earlier.)