Disbanding/withdrawing is more complicated than it appears on the surface.
First you do not have to remove any unit from the game BUT it costs an horrendous amount of PPs not too.
Below is the nitty gritty but there's more here
https://forums.matrixgames.com/viewtopi ... 3&t=396274
Air Unit Withdrawals or Disbandments (5.1.4.3)(7.2.2)
Collectively all are removals from the game.
The basic idea was a disbanded unit leaves the game, a withdrawn unit comes back later. Wish it was as simple as that
as many units can do both!
Some are scheduled by historical circumstances, others by choice due to the game situation, some return, some don’t,
some remove pilots, some don’t, some are affected by removing early, some not. Sometimes you can withdraw when
you should be disbanding and vice versa. It can get confusing, hopefully this helps.
Generally:
• You can voluntarily withdraw or disband most air units at any time.
• Air units (apart from fragments) assigned to ships at the start of any scenario are not allowed to disband even
if transferred to land. This does not affect fragment nor any air unit assigned to operate on land that is
transferred to a ship. They can still withdraw.
• You cannot disband a unit if it has an active detachment. Note: Detachment are only present at the start of
any scenario, you cannot create them during game play.
• If the base has less than 20K supply all aircraft are lost indicated by the red withdraw and disband button.
• Air units returning as reinforcements come back in their National Home Base with what it left with in terms of
aircraft and pilots.
• Returning air units lose any Perm restricted [R] status they may have had when leaving unless the scenario
specifically keeps them. If this did not happen all returning air units would be stuck in their National Home
Base and any location attached to it.