desertopsguy: quite a few private a/c fly under an AOC purely for tax / fuel reasons, with no paying pax, as you must know. Depending on the mission profile and bases operated to, this may make sense at one time and not another. The Danish authorities in particular are flexible about taking a/c off an AOC temporarily for purely private flights... for less flexible authorities, I can see why it makes sense to remove an a/c permanently from it.
Removing an AOC from a whole company is pretty unusual I guess, but I can imagine a scenario where it would make sense, for example if the company is small, or there's not much charter business.
Not qualified at all to judge on whether it's possible or not, but I can't see why it wouldn't be!