DAL has the same policy.

Bottom line treat any major airline (and any company associated with them including wholly owned regionals and ground handling services) with kid gloves in all of your dealings with them. The number of airlines is shrinking and if you burn too many bridges you might find yourself in career checkmate. Very stupid to blacklist yourself over something as trivial as a timely/respectful resignation or decline of job offer. Do it in writing...if time is of essence then call abd follow up with a letter. Give them two weeks notice AT THE VERY LEAST.

I know a military guy who lost a CJO because of something like this that happened years in the past before he even joined the Navy. Didn't give two weeks notice as a ramper in his small hometown...the station was handled by a wholly-owned regional which no longer exists but the major STILL had the records. Actually he says he did give notice but somehow there was confusion and the supervisor put him down as not eligible for rehire. This is a great dude with master's degrees and all the gucci top gun boxes checked but he got torpedoed by something a bull ramper with a GED did 20 years ago.