Soldiers Effects Registers - meaning of 12/20 (a/c) code numbers?

[clive_hughes]

Hi,

I'm used to checking the Soldiers Effects Registers online, but for the first time I've come across something I can't decipher.

The man in question was a 1914 volunteer in a Line battalion, and went missing with others during the March 1918 German offensive.  No known grave.  His main record file was presumably lost in the 1940 Blitz. 

His Effects record states that he was "presumed dead on or since 22.3.1918" and gives the amount of back pay plus War Gratuity as usual.  However, no next of kin beneficiary is stated.  Instead, there is a note ""trsfd. to 12/20 (a/c)".   The others on that page of the register have the same 12/20 a/c codes as well. 

He did have surviving parents who appear in his file, his father being the stated next of kin, so can anyone enlighten me as to the use of this code, please? 

Clive