Not forgetting Plymouth School OTC who the badge long after both regiments had gone. It is recorded in use at the OTC in 1938 as a black PofW feathers badge. Of whose design and what the fittings are unknown. EJ Martin's article on OTCs said Plymouth College wears 'exactly the same badge' as the 15th London regt.
http://www.britishbadgeforum.com/for...162#post401162
A picture of the badge being worn by Plymouth College OTC to back up E.J. Martin's article.