How does an E6 have 6 service stripes?

Prior service where the break in service was long enough to lose rank is one possibility

I retired with 20 years active, 1 yr National Guard and 3 years Reserves for a total of 24 years of service. I retired as a Staff Sergeant. No, I didn't get any article 15s Yes each time I switched back to active duty I was reduced back to E4. The reason I didn't get promoted to SFC was because 1. there were only 600 FA Surveyors in the Army which leaves very limited amount of SFC slots, 2. I opted not to go to ANCOC because I liked where I was at. So, I retired a Staff Sergeant with 8 service stripes. 6 AAM's, 5 ARCOM's and MSM. When I first came in it wasn't uncommon for people to not even make SPC in their first tour.

There are several scenario 1 being the same as mine. I had 7 years of active duty service and then got out. After a 10 year break I joined the National Guards, the fact that I had over a 5 year break in service they put me back in as a Pfc with the understanding I would make E5 with a good 6 month Eval (On Contract) along with having to go back to BT all over again (Ft. Lost in the woods which was a joke after being 11B1P and a L.R.S team member) 45 day's after returning to my unit I was promoted to Spc and did not see my stripes for another 1.5 years. I did not care as I joined because I wanted to be back in the military but not full time as I had a career. I did learn quickly that it was hard for soldiers to make rank in the National Guards as spots are far, few, and in-between. I was medically retired in 2014 with 3 tours and 17 total years of service and retired as a SSG as well with 1 year shy of 18 years. 85/88 96/2000 2004/2014

There are several scenario 1 being the same as mine. I had 7 years of active duty service and then got out. After a 10 year break I joined the National Guards, the fact that I had over a 5 year break in service they put me back in as a Pfc with the understanding I would make E5 with a good 6 month Eval (On Contract) along with having to go back to BT all over again (Ft. Lost in the woods which was a joke after being 11B1P and a L.R.S team member) 45 day's after returning to my unit I was promoted to Spc and did not see my stripes for another 1.5 years. I did not care as I joined because I wanted to be back in the military but not full time as I had a career. I did learn quickly that it was hard for soldiers to make rank in the National Guards as spots are far, few, and in-between. I was medically retired in 2014 with 3 tours and 17 total years of service and retired as a SSG as well with 1 year shy of 18 years. 85/88 96/2000 2004/2014

It's simple. He has an MOS that has limited promotion opportunities. My MOS was an MOS that fed into 63Z. Competition was across the 63 CFM. I know of SGT E-5 who had 20 years and no UCMJ problems. I retired E-7 with 22 years and 7GCMs. E-8 was hard to make in the 63 CMFs.

Likely the staff sergeants time was not all on active duty. There may be some Reserves or National Guard time in there too.

Got out came back on or did timr sd a reserve

There are many factors to consider. I have been in the army for 20 yrs now which I had reached the rank of E5 and then switch to become an officer and now currently a MAJ to which I have met many outstanding soldiers of all ranks and years of experience having served in active duty, national guard and Reserves myself.. You have to consider the any career paths that soldiers take for either their own personal interest or ambitions. Some have done active duty time and then switch to either national guard or reserves. National guard for example has a very slow rate of promotion. I met many soldiers from E4 to E6 with 16 plus yrs of service and its due to no available promotion slots in their MOS in their state. I even have friends who have been in the reserves that i known since 2005 when i was a sergeant with them and they are still E5s today because they remained in the medical service MOSs. Never judge a person by their rank and years, every individual has a story and experience and you never know if you may have life changing experiences that pull you into similar situations. I was a PFC back in 2000 and im glad I had a few mentors that taught me this lesson. Keep strong and seek mentors my young green brother.

As a 42A ,and since clearly you've gotten past the 3rd grade and can multiply 6 x 3...what's the BS point of your question?

Maybe he has prior enlisted service in one or more other branches.