For one thing, you begin collecting Reserve retired pay at age 60 not 63 and collect as early as age 55 if you have been mobilized after 2022. You can deduct 3 months from age 60 for every 90 days mobilized or deployed since 2009.Any active duty time like AIT, basic training and any annual training performed will adjust your basic active service date, so that does count towards your 20 year retirement active duty retirement.Your weekend drills days gets added on the back end after you have completed 20 years of active federal service (AFS). 48 drills (4 points per weekend drill) x 3 year is about 5 months roughly, so retire with 20 years afs, they would pay you for 20 years 5 months of service.The 3 years od reserve time counts for longevity raises. E4 over 4 years, etc.