If you are getting close to the match, you should realize there is a difference between ERAS and NRMP. Two separate programs, two separate functions.
ERAS is for compiling and submitting applications for interviews. After submitting your application and the list of programs to which you would like to apply (include both civilian and military) you will receive interview offers, schedule them, etc. Military residencies use ERAS just like civilian residency programs because it is easy and standardized. You will have to do your military interviews before Oct. You should schedule your civilian interviews for after the middle of Dec.
Then you match.
Each branch of the military is slightly different but somewhat similar. I am in the Army, so I will tell you about them. Sometime around the middle of Oct (if I recall correctly) you submit your wish list via your mods account. You also ask at this time for a deferment if so desired. The boards meet after Thanksgiving and the results are published (on the website for the Army) on Dec. 18.
NRMP is the "civilian match" where you compile an ordered wish list that goes to a supercomputer that fell from the sky, presumably from outer space, and landed in Iowa or similar non-descript/non-confrontational state that takes your list and the lists from each program and matches you to a program. Your list is due in Feb and the match occurs in March.
You can see why you would want to schedule your civilian interviews for after Dec (i.e., after the military match) because that is when you would find out whether you got a deferment or not.
NB. DO NOT REGISTER FOR THE NRMP UNTIL YOU ABSOLUTELY HAVE TO OR AT LEAST AFTER DEC. 18. The military will not reimburse you for the cost and it would end up being wasted money if you match in the military. This is a lesson I learned the hard way.
ps. this time course gets trickier with the early match programs - neurosurg, uro, ENT, ophtho, etc.