I was in the DEP for a year before my departure to basic. None of it counted toward my enlistment. I did receive a temporary military I.D. while in the DEP. It was black and white(instead of green like active and reserve I.D.s) and said Delayed Entry on it. I was able to get on base and use the facilities like the golf course, bowling alley, etc. It also showed me as a Pvt. 1st class, because of my 3 three years in JROTC and score of 89 on the ASVAB test. None of that counted toward time in grade either, nor was I paid. That may be why your friend is confused.
Chief Wiggum: This is Papa Bear. Put out an APB for a male suspect, driving a... car of some sort, heading in the direction of, uh, you know, that place that sells chili. Suspect is hatless. Repeat, hatless.