So for some reference. I got order of merit wait listed for a year due to all reserve slots for AOC being filled for the year after my packet hit the board. Then I had to re-board for the next year and got a slot. I commissioned in December. I didn't get orders cut until the end of April. That was before all the IPPS-A issues.
Now as a company level S1 I will tell you IPPS-A is a complete charlie foxtrot. We haven't been given half the stuff we were promised with IPPS-A. Tons of stuff has disappeared from records (and even though we told our soldiers to make sure they had paper copies and electronic copies of everything several times before the IPPS-A conversion of course most of them did nothing and now they are missing stuff). S1 and S3 are overloaded across the reserves right now. Many of these folks handling these issues are also not full time folks so we have other jobs too full-time.
APMC is having the same issues, but as others have said civilian workforce in the DOD is very lackluster usually. I have my own gripes about APMC (and being attached to them), but I won't go into those. Suffice it to say things are a mess for everything to do with personnel right now.
Hang in there. It hasn't been that long in military time for you even when things were going as they typically do, but you are dealing with the DOD during a chaos time so extra patience will have to be had.
I would also caution you about going the IG route. You don't want to start making waves before you even get through the door. IG isn't going to do anything at this point other than say "you need to wait and be patient. People are working on it. It has only been X number of days, IPPS-A is being rolled out, etc. etc. etc." and then you also risk pissing off some of the folks that you are going to have to depend on for a lot in your career. If they feel you are a problem to deal with (Yes I know it's crazy that expecting someone to do their job makes you a problem to deal with!) then trust me they can make your life miserable. I've seen it happen.
Just hang in there and be patient. You are learning a valuable lesson here early. Always have a course of action A, B, C, hell maybe even D to deal with problems especially financial ones because I can tell you Uncle Sam will mess up orders, they will mess up pay, and you will be the one who suffers when it happens.
I say this as I just spent this morning tracking down folks in APMC to get a 1380 status update for pay and points I submitted almost a month ago and haven't received anything for yet. It's going to happen. Sometimes you just have to realize the system sucks and nothing you can do but push a few folks as politically correct as possible and have some patience.