(e) 21st October 1940, Records indicate she is now under Western Command
After that, the Service record is illegible,

We do know for certain that she was transferred to Alton
Staffordshire to an Officer Cadet Training Unit.

However these units were not operational at Alton until 1941.

Whilst there her service record indicates her as "Mess Hall Assistant"

When ATS girls were attached to an army unit, they displayed the badge of the Unit over the left breast pocket .The wreathed ATS badge was worn on the cap and a small ATS on each shoulder.

The picture of Katherine outside OverHall Farm shows no badge on her uniform, at that time she couldn't have been attached to any Regimental Unit.
This must have been before, she was attached to the 121st Middlesex Regt,

Possibly, just parading her nice shiny new uniform for the benefit of those at home

http://www.altontowersmemories.net/page4.htm
Quote from page:-

Officer cadet training started at the Towers in 1941, although
apparently there were soldiers stationed there earlier, possibly
Polish. Permanent staff at the Officer Cadet Training Unit (OCTU) were in the main from the machine gun regiments: Royal
Northumberland Fusiliers, Cheshire, Middlesex and Manchester regiments, although a few came from the Kensingtons, the
Territorial Army Machine Gun Regiment. The course at Alton OCTU lasted 27 weeks.

This confirms Middx Reg at Alton during 1941


Extract taken from the memories of a Cadet at Alton Towers

........................................

We filled in a few forms, and had a speech of welcome from the R.S.M. who to my surprise said the permanent staff (including the A.T.S.) had an inferiority complex and we should therefore be friendly and attend their functions.

...........................................After a short break we handed in our
eating irons, here plates, mugs etc are kept in the dining hall, all meals are served by A.T.S. who it seems are billeted down in the village.

From this we can see, that the ATS personnel carried out domestic
duties together with other ancillary work such as driving and ground maintenance.

".............In 1938 ladies who volunteered were sent along to the
local Territorial Army units that already existed in their local town"