I submitted my secondary early (6/27), and haven't heard back yet (no "complete" email either, just a "secondary received" email). Issue is, I think I am not yet being reviewed because while I am otherwise complete, I am awaiting a LoR from a PI with whom I'll be working with in the coming year, and has agreed to write in support of me. My school's committee letter is already in.
I listed the letter, however I don't expect it till August-September. Should I email Einstein and ask them to continue with review, or do I have no choice but to wait for the final letters receival? Just seems a bit of a waste of an early app, when everything else is already in hand and good to go.