Interest question if paid after the 1st

[Lucas Hammer]

So I'm in my first ever mortgage (house hack in Chicago) and my mortgage is being serviced by Chase. The due date is the 1st, but on their website, it says that there's only a late fee if I pay on the 16th or after. My question is whether or not the total interest will go up if I pay on the 7th instead of the 1st. I'd like to collect rent on the 1st and then pay the mortgage on the 7th to prevent the lag of pulling money out of my property account just to put it back in within a day or two, but I want to make sure that my interest won't go up in the 6 additional days if I pay it on the 7th.

Can someone let me know if that makes sense or if I'm misunderstanding how mortgage interest is calculated?