Thanks everyone!
Exactly! That is why I'd rather avoid the ADIT stamp, if I can. When I called USCIS yesterday, the agent offered to set up an appointment but I stalled and said no.
Sounds good, I'll wait.
From what I'm reading, the whole issue about needing a I-797C for travel is that airlines want to see the original copy to allow boarding. CBP, on the other hand, doesn't seem to care about it, and I'm reading that using a printed copy is fine. If true, this would make my life a lot easier