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Which is why most (if not all) programs are extremely understanding.</p>
<p>Speaking from my own application experience, one of my letters didn’t arrive at one of the programs to which I was applying – probably a snafu with the mail. The deadline was early December, and interview invitations went out in early January. Right after New Year’s, they contacted both me and my recommender to let us know the letter was missing; he faxed it the next day, and I got my interview invitation the day after that.</p>
<p>As a digital example, my boss turned in a recommendation letter late for a technician in our lab applying to my own program, which uses an online application system. The system closes for applicants on the deadline, but remains open for recommenders to submit their letters. My boss knows this, which is why he was able to be so nonchalant about the deadline.</p>
<p>I’m not saying that you shouldn’t remind your recommenders about deadlines. But repeated reminders, when it’s clear the professor in question is aware of the deadlines, are unprofessional, immature, and out of line.</p>