I had this done to correct some awards and a few other things on my DD-214 and it took them 9 1/2 months to finish it and send me the corrections. They pulled my service record for the duration and preparation for the board and no other use was allowed until they finished. If you will need access to your service records, just remember that they will not be available once the process starts.
Good to know, Mbstroz. Once I am in the system I plan to get this started. I have 2 medals that I received from my active duty time that are not on my DD-124. Fortunately, I have the paperwork needed for that part...at least I hope what I have will suffice!
Another question I have is how would this affect the year I can retire, if I reach that point? Would the extra three years be counted or would the government only count the 4 years of active duty.