Concur with GSSTEP. It's hard to wait. Did Emerald coast with GSSTEP in panama (I think there were 3 Marines in a room of 50 folks ). I did gov't contract work on a King Air 350 for a few months in west Africa after getting off active duty to get my multi time, get a type rating, stay current, and get some decent money too. It was hard work, but worth the sacrifice. Just a plug for contract work, but every dude I know who wanted Delta and worked for L3 or CAT got hired, my $.02 as well.

Get as many internal recs as possible. I also understand that DeltaNet now has a link that active pilots can click on and recommend an applicant, which is supposed to trigger a review. If you know someone inside, might be worth asking the question; a good buddy of mine said one of the instructors showed them how to do it during indoc.

App published sept '13
Left active duty jun '14
Fix it email jul '14 (high school GPA)
Invite to interview 11 Nov
CJO 10 Dec

Keep the positive mental attitude and even if you don't have the invite, start preparing because an invite is inevitable.