Bad things. You would probably be denied boarding when you showed up at checkin anyway - DEPUs don't waltz up to the counter themselves. Also, most airlines have a maximum quota of DEPUs that they will accomodate on a single flight - if that is exceeded you will be left behind. Some routes are more DEPU-intensive than others as you can imagine.

DEPA is one step up from DEPU. Only the really nasty pieces of work get to be DEPAs. They are always fun to have around. Imagine Cyrus the Virus from Con Air, but with 2 guys in business suits on either side. Maybe you should send a DEPA SSR and then tell checkin that you ate your escorts. That would be good for a laugh.