You will need the DodMerb to be performed prior to board review. It is a part of the packet since there is no reason to offer a scholarship to a candidate that is not medically qualified.
Additionally, there is no thing called PMS, they are called ALOs. The ALO will interview prior to the packet being submitted. They will actually write a rec for your packet which is a part of your WCS.
You need to clear the 1st hurdle by being qualified as a candidate. From there they will ask for more things to be submitted, and then that will become the official packet.
Caveat: this is how the system worked in previous yrs.
Caveat 2: You may see candidates being further down the path than you because many AFA candidates also apply for AFROTC. Their Dodmerb and ALO files will be duplicated for the ROTC board, thus the only thing that is truly different is they take a PFA instead of a CFA. This makes it a faster process on the whole than for those who are only applying for ROTC.
AFA candidates traditionally have all of that done by the end of summer, and their fall is spent requesting noms. That allows the ALO to tell divert their attention to the ROTC candidate, since they have already submitted their recs to the AFA board by early Oct.
Caveat 3: At this time, if you know of any medical issues, get that paperwork in order. DoDMerb is traditionally not done by your family doc unless your family doc is DodMerb certified. They will give you the option of a select few to have this performed by. If you are military, you can call DodMerb and ask them to change it to your military doc on base/post.
You will have not only a check up, but this is head to toe and everywhere in between, I mean it is everywhere. If you try to hide a medical issue, they will find it. Don't hide it because it will put you behind the 8 ball for getting a waiver. If you know that you had asthma at 4, but no longer have it now, address it with MullenLe now. If you know that you have taken prescribed medicine for a chronic health issue, find out now if that is a waiver issue.