I find it odd that a Colonel retiring after 37 years wasn't bumped up a grade.
One of my old CO's retired a general after a bird strike in a huey ended his career as a pilot. That sort of courtesy bump in grade is not uncommon, especially if you are a "political" as Muthra is or was.
In the Air Force it's called a tombstone promotion. One of my old bosses got one.
"Tombstone" promotions ended a while back.