The Unissued Airmail Stamp of 1922

Austrian catalogues list here an overprinted stamp which was to have been issued on 23 October 1922, for use on airmail. ANK designate it as (5). This was the 2Kr value in milky blue of the 1920-1921 definitive issue, overprinted by typography with the word Flugpost. 474,500 pieces were overprinted, but because it was then decided to issue the "Falcon and Kress" air mail set on 31 October 1922, the overprinted stamps were not issued. Also, it is a Deutschösterreich stamp!

Two different plate errors are known; both are a malformed s in Flugpost.

The official story is that these stamps were officially destroyed and only 250 remained. This seems implausible, since not only do several colleagues have copies but in 1912 the Austrian Post Office was offering for sale mint singles and blocks-of-four! Maybe it was 250 sheets?