In any%, when to stop timer, in some videos without the Dethl skip, some stopped the timer when touching the stairs, while others waited until they got above the boss room. Any rules about this?

Timing ends as soon as the screen is completely white when going up the stairs.

Thank you, but that means that some of the submitted runs should get anohter time because the timer was stopped when they touched the stairs.

We made a change to the rules about a year ago to end time on the first frame that the game has faded completely to white (exactly 150 frames after you touch the stairs). You'll note that most of the (older) Any% videos have a comment to the effect of "New timing makes this a X:XX" or something of that sort.

I missed the comments about new timing. Thank you for your reply, it is great with clarified rules. I don't think I am able to count 150 frames exactly, but I guess it is not a big deal if you wait a little bit too long to stop the timer, rather than the opposite. Correct me if I am wrong please. When the screen is totally white you can stop the timer and do not need to wait anymore, got it.