Origin of the Divisional Rest Station in 1914?

[David_Blanchard]

I am trying to find definitive evidence of the origin of Divisional Rest Stations (DRS). ( sometimes called Convalescent Rest Stations) 

A recent book, ‘The Weary Road’ (2019) by Mark Osborne Humphries has part of a chapter entitled- ‘The Divisional Stopping or Rest System’ - where the author says the first DRS was set up as an experiment by the 3rd Corps in November 1914 and then implemented by DGMS Sloggett in early 1915 for all field ambulances to set up a DRS.

 

I have looked at the footnotes included by Humphries in his book as well as the WD of the DGMS but cannot find  an order issued by the DGMS that required field ambulances to set up DRS.

Any help appreciated.

 

David