This isn't the first time he's fallen. Time stop doesn't affect him so if he's midair and pauses he will fall down just the same.
I was wondering the same, but maybe he's emboldened by the fact that what he's doing right now in the past has (seemingly) no consequences for the present.
I never thought I would enjoy so much this manga... considering its initial premise, lol.
Also, and I don't know if I'm the only one, but the Hag has grown on me. She's got the cake, too.
But then it would be a matter of if he could get an hold of her while falling, because if he isn't quick he is still going to fall on something very hard.
Time loops like this are something you've gotta be careful with, or they can become terribly monotonous (the worst example being the "endless eight" fiasco).
Despite going over the same beats again and again, it really does feel like it's ramping up tension and we're peeling down to the core of the matter - that's to say the time loop is being handled well.