Number of aircraft produced - data dance

I have observed the number of units (aircraft) produced of different models (Quantity produced in A/C info page) dances up and down. This seems strange, as once the metal is produced, it should be counted without further variation, no? I

ask this out of pure curiosity, as I cannot understand where the missing aircrafts go.

Example: Sukhoi Superjet 100-95 production showed 238 units in October, now stands in 218.

Presumably, this is a newer game world that has the immediate delivery program?

To prevent abuse of the system aircraft delivered under the IDP, disappear if a company is shut down.

The reason for the presumption is that you would get 5x Sukhois for your initial $10mil. So 4 airlines shut down, with 5x Sukhois delivered by IDP each…that gives you 20

you can have aircraft ‘disappearing’ also on old servers. AS deletes aircraft if they are ordered but returned shortly after. when the 767-200 was discontinued i tried to order new ones and release them before or shortly (about one week) after the delivery, the aircraft never went to the aircraft market and they were deleted. i asked the support and it seems to be part of the cheating prevention.

I am on Ellinikon and yes, there is IDP there, so that would be the reason why, as you explained. Thank you for that, I had no idea this was so. I think it is quite reasonable and it does prevent cheating.