MPN....when an Officer gets passed over for promotion the third time and is confronted with being removed from the Army....many reverted to Warrant Officer Ranks depending upon what was offered to them.
The joke was "How long does it take to make CW3? Twenty Years if you start at Lieutenant.".
Mind you....the Senior Warrant Officer Rank is CW5.....so upon reverting to CW3....the LtCol took a small pay cut and gained a lot of prestige and respect upon becoming a Warrant Officer.
As a CW2 I was offered a Direct Commission to 1st Lieutenant....but turned it down as I knew come RIF time post Vietnam those of us that took those offers would be the first to be cut unless we had completed both Officer Basic Course and the Advanced Course.
Those schools were not going to be offered as the need was for combat unit service in Vietnam with no guarantee it would be in Aviation....and would likely be in Infantry units upon completion of the Basic Course.
Turns out I was right....vast majority of those that took the direct wound up back as Warrants or just plain Civilians.