Really confused about recs and Common App..

<p>So just to get straight to the point, one of my teachers wants to send a rec through postage, but the other likes the Common App. How can I submit my Common App when it says "Before submitting the CommonApp to this institution you must:
Assign your School Forms recommenders to this institution " when one of them doesn't want to use the Common App?
Also, one a related note, how will I know if Yale received my recs if I don't have an Eli account because of the Common App problem?
Thanks in advance.</p>

<p>1) you assign only one. It won’t prohibit you from moving fwd if only one rec writer is assigned. 2) They have status updates. Plus, if anything is missing and a crucial deadline is approaching, they will contact you or the school and ask for it. Simple, no?</p>