Hi,  My information is from Steinway archives.

11/20/14 -- First V (K Vertegrand scale upright for Aeolian Player),
serial number 169554.  Aeolian called this the Style S upright,
designating this as the upright player.

10/19/29 -- Last upright from Steinway to Aeolian, serial number 274793,
Again the V (K Vertegrand scale upright).  Aeolian again designated
this upright as the Style S.

1914-1929 Steinway made for the Aeolian Company models Aeolian Style S,
Steinway Style "V", K vertegrand scale; V identification not explained.
Player mechanisms within the piano, expanded and heightened case 4'5"
of a Sheraton design similar to regular production.

One very interesting fact is that Steinway had held two Model AR's that
were built in 1925.  They were finally shipped to Aeolian in 1935 for
the Duo-Art player, and they were assigned 1935 serial numbers (serial
numbers 279124 D2205 and 279125 D 2203).

Another fact (other than some rare later installed Duo-Arts, or the
Ampico systems in Steinways) was the fact that the last Steinways
built for Aeolian were shipped from factory 10/30/31.   Again, these
pianos did not get assigned serial numbers until they finally had the
Duo-Art players installed in them.

I own a 1930 XR with electric roll drive (Steinway records state built
10/30 and shipped to Aeolian) that shows a 1933 serial number, #276375
J756.  The estate from where it was purchased said that the first
owners bought this "new" in 1936.  Because of the depression, I suppose
the piano sat for a number of years at a piano dealers store.  

Steinway also built the more "normal" non-extended case grands for
the remote Concertola system.  These were designated "Y" grands.  After
4/7/1933 Steinway terminated the contract with Aeolian to build the
player equipped grands.   At that time Aeolian had bought 241 "Y" type
grands for the remote Concertola installation.  These were never
installed and were returned to Steinway for resale as straight pianos.
Of these 241 pianos 201 were the model M, 39 were the model L, and one
was a Model A.

Because of the depression, Steinway stopped building pianos in the fall
of 1931, and did not resume piano production until 8/7/33.

1/3/40 -- special order S grand to the Aeolian American Corporation for
the Ampico Player.  #300022 Q2415, regular stock case Sheraton.

4/2/41 -- special order S grand to Aeolian American for Ampico player,
#306766 R380, regular stock case Sheraton.

And for those who may have interest in the "Y" Concertola pianos:

3/13/31 -- last M grand for Concertola #272429 J2426
4/21/31 -- lone B grand for Concertola #272311 K503
6/24/31 -- last A grand for Concertola #275936 J2704
7/2/31  -- last L grand for Concertola #272587 K848

Gary Hanson