Inspector of Army Schools or Indian Army Unattached List Officers Cap?

[leigh kitchen]

I'll post this in the Head dress section, rather than the "what is it" section although I'm not sure what the insignia indicate.
When I bought it, the vendor thought it may be the cap of an officer on the Indian Army Unattached List, whereas I veered to wards it being a cap of an Inspector of Army Schools.
Although my reference for this is the 1900 Dress Regs the description of badge & buttons fits, albeit this cap has the later KGV cypher & king's crown buttons rather than QV insignia.
Can anyone tell me which it is please, or whether it's something else?