Rod,
As usual, first a little background.
After WWI, aviation was largely verboten in Germany. One of the casualties of this restriction was German aviation pioneer
Hans Grade, who had previously run a flight school. Since he couldn't run a flight business, Grade went into real estate, opening a hotel and restaurant in
Borkheide, a small village in Brandenburg. he named the hotel and restaurant Fliegerheim, or Flyer's Home.
In the period after WWI, a series of cinderellas were produced with the text "Für's Fliegerheim" and featuring aviation, military, and political figures from primarily Germany and Turkey. It's not clear if they were to benefit the hotel and restaurant, or the Borker Verkehrsverein, a local social organization for former German pilots which frequently met at the Fliegerheim.
All info and photos below are from Charles Kiddle's
Poster Stamps / German Aviation / 'Zeppelins' or its companion volume
Poster Stamps / German Aviation / German Aircraft. Photos open to large versions.
There were at least 7 series, and all were believed to have been issued in blocks of 20 (10 wide x 2 tall).

Kiddle WW28 Block

Kiddle WW31 Block

Kiddle WW49 Block

Kiddle WW70 Block

Kiddle WW91 Block

Kiddle WW91b individual stamps
The rarest of the blocks is this one of slightly different design.

Kiddle WW112 Block of 10
Kiddle notes that he himself had never seen it in a full block of 20, so the exact composition of the Block of 20 was unknown to him. He speculates that the other half was this block of 10.

Possible other half to Kiddle WW112
Your single cinderella catalogs as Kiddle WW72, with a rarity of '10', which means its pretty common.
Also, the Fliegerheim is still an operating hotel and restaurant --
Filegerheim.