Can anyone explain if this guy I know is pretending to be a LTC?

Really doesn’t bode well for you as a CPT to be as uncertain as you are about how legit your friend is. Demoted ahead of peers.

I think I know what the BS stands for. Just sayin'.

Seems like his BS isn’t for nursing.

He has BS in nursing??? Sounds his BS is bull shit.

I’m going to go out on a limb here and say he’s about as legitimate as Epstein’s suicide. He could be new to the Army as an O-5 IF he were a cardiothoracic surgeon; we had plenty of those at Ft Sam. As a 45 y/o with a BSN? Those first 2 letters say it all...BS

Oh yea I was stationed with the 101st Airborne/Air Assault 1984-1986 and if my memory is still good the 101st are at Ft Campbell KY

It is possible depending on his MOS. If he has the education and experience he can be brought in at a high rank. During Desert Storm I met a physician that was brought in as a COL. (Needs of the Army.)

depending on the degree in nursing, medical people get promoted quite rapidly. MDs part out as Cpt and make Major within 2 years

He seems to have more than a BS in nursing. Why don’t you call his unit one day and ask for him. Even on a non drill day there should be an admin type there.

I was a staff officer as well; I was a Chaplain. As such, I went through abbreviated officer's training for Chaplains, Doctors, and Lawyers; at the time it was called Air Force Officer's Orientation Course and lasted two weeks. It is probably the quickest commissioning program the Air Force had at the time. Active duty and Reservists were in it. I was a Reservist assigned as an Individually Manned Augmentee (IMA) to an active duty unit. Since I was fresh out of seminary I only came in as a First Lieutenant. Those who were older and had more experience came in at higher ranks, but the highest I in our class was a doctor who came in as a Captain.

So ... I can see them coming in as a Reservist. At age 45 they probably got their degree when they were 22, so that gave them 23 years experience as a Nurse, so I can see them coming in at a higher rank. I assume that the Army has an IMA program equivalent for reservists so I can see them being assigned to an active duty unit.

Let's say that person's nursing expertise was in something the Army was critically short of, like maybe a Nurse Anesthesiologist or maybe a Surgical Nurse. In that case the Army might have offered a higher rank as an enticement to come in. Our youngest daughter was born in an Air Force hospital (March AFB, CA) and the doctor who delivered her came into the Air Force as a Lieutenant Colonel. She was from South America and English was definitely her second language, but there she was.

So, could your acquaintance actually be a Lieutenant Colonel reservist attached to an active duty unit? Yes, they could. But could they also be full of fecal excrement and not be what they claimed? That also could be true.

From what you have told us it is impossible to know for sure.