Charles,
the following held the rank of major in 1916-17
Hippolyt von Kiliani (7 January 1914)
Konrad Prinz von Bayern (10.9.14) à la suite
Heinrich Rhomberg (3 November 1914)
Eckart von Pappus und Trazberg, Frhr. zu Landenberg und Rauhenzell (19 May 16)
Heinrich Prinz von Bayern (serving with the Infanterie-Leib-Regiment)
Karl Ritter von Gonnermann (18 January 1917)
The remaining officers shown as Major a.D. in the list above were post war promotions beginning with Ferdinand von Kobell on 19 August 1919.
A couple of officers à ls suite der Armee with the uniform of 1. SRR also held the rank of major at this time:
Friedrich Graf zu Pappenheim
Siegfried Graf von Pückler und Limpurg.
There may be others lurking in the background such as recalled officers.
Regards
Glenn