For Pharmcas, once you e-submit it, you can still go back and add letter of recs right? But if you've submitted it near the deadline and then add letter of recs later, how would the pharmacy school get the letter of recs in time?
To answer your first question, yes. You can still add references as you would normally after e-submitting.
As far as submitting them by the deadline, I'm pretty sure your schools need to receive everything by then. If your reference doesn't submit their letter by the deadline.. you'd probably be out of luck 🙁.