[78-L] HMV matrix symbols

[S&R Pinsker]

There being a current kerfuffle over a singer with a swastika tattoo,
I recall that the matrix numbers of some HMV electrics  included a
swastika, others a triangle. One is Schnabel's Beethoven Concerto
No.1, recorded at Abbey Road in 1932. The matrix prefix is 2B instead
of 2EA. What is the significance of these symbols and what is the
difference between B and EA matrix numbers?
rdp