Hey all,
Don't know if this is helpful (or just likely to induce more anxiety), but you can call Fedex (even if you don't have a tracking number) and convince them to tell you your tracking number and the date a package is posted:
My conversation:
Me: "Hi, I'm ringing about a letter that was posted to me on the 10th from New York, it hasn't arrived yet and I'm getting concerned"
Fedex: "Do you have a tracking number"
Me: No, but I've been assured it was sent, I live at...
Fedex: Hang on, I'll just check the system
Fedex: No there's nothing for that address posted on the 10th
Me: Oh? That's strange - could there have been a delay?
Fedex: I'll just check the next few business days - oh no, wait I have something coming up which was posted on the 16th
Me: Oh that will be it! Thank goodness there's some record!
Fedex: Alright, I'll give you the tracking number so you can keep an eye on it...
So that is how you can find out if anything has been sent without contacting the school. Positives include knowing when the letter will arrive roughly - so life can resume. Negatives include knowing when the letter will arrive roughly and experiencing extreme anxiety over whether it's a good letter or a BAD letter.
All the best to those still waiting (solidarity!)