What and where was 'B/MVDRR'

[Tony Stanford]

I have a 1937 cover from the British PO in Larache, Morocco addressed to 'B/MVDRR, LONDON' and would like to know the function and location of this organisation, which I assume to be military or diplomatic.  Many thanks for any help, Tony Stanford

[Peter Harvey]

Hi Tony,

I don't know, but my initial thoughts were MV = Merchant Vessel or MV = Mechanised vehicle, but I have not got a clue about the rest other than 'Motorised Vehicle Despatch Rider', however I am sure others will chip in?

Peter

[Graham Mark]

Hello Tony
This looks like a mail box facility.  Some companies set up a service whereby their customers could use such an address and according to the customer's wishes the mail could be held or forwarded. 
The CCSG had an article back in 2013 which can be accessed in the Global Philatelic Library through the RPSL website.
Dennis Rosser & Graham Mark "WWII - GB - British Monomarks Ltd"  vol.40, No.3, p.86.
Unfortunately the illustration which accompanied the text is not too clear.
In this article reference is made to earlier articles which included questions about the mode of address, with examples used in wartime with and without censorship.
I hope this helps
Graham