As a better alternative to my method above, would it be possible to have something like
mySQL events? They're said to be able to be an alternative to cronjobs and I have seen options for this in phpMyAdmin, but I've never touched them. I'll try it and see how it works out.
EDIT: Nevermind, you would need super privileges in mySQL to make schedules (basically add permission), which I can't find a way to do.