Love the French Defiants - another one for the why-didn't-I-think-of-that list.
I thought Kwangsi AF was independent and used the triangular markings for a bit after 1934?
Lennart Andersson's “A History of Chinese Aviation” has a section on the Kwangsi Air Force and most of the photos do show aircraft prior to 1937 with a large triangular marking.
The triangle appears to have been white with a thick black border but on some aircraft with dark coloured fuselages (Wapiti, AW-16, Avro 637) the triangle colours are reversed and there are also some machines which appear to have a black-outlined white disc instead of a triangle. So no RLM or Air Ministry civil servant types in Kwangsi then - - -
Also, most photos show only the fuselage – the only photo giving a clear view of the wings is of a crashed Avro 631 which has triangles on its fuselage, a triangle on its port wing upper-surface and a more conventional Chinese star on a red-outlined blue disc (as in Apophenia's AW profile) on its starboard wing!?!?!?