Hi Laura, Assuming I'm guessing correctly which alert you're referencing, that setting is a global setting in the Setup screen, under Email, then Automatic Reminders. Unfortunately, it is a global setting for all users and not individually configurable. Our team share your annoyance, as our timelines frequently change as well. I've not found a good middle ground, though I've considered disabling it entirely or making the timeline much more generous (say one week late instead of one day).
Katherine Stibley