Disc headcodes

[GWRPannier1501]

My question does not refer to the Southern Railway, and later Southern Region‘s headcodes, nor any of the pre grouping companies disc headcodes. I would like to know the meaning of the black discs found on the Longmoor Military Railway and I believe the BR WR, usually with a white letter or number in the middle. What do they mean?

 

[Clarence Yard]

Duty numbers. The 15xx is on No 2 pilot at the Oak which usually worked a number of ECS (or “ups and downs” in WR speak) between Paddington and Old Oak as well as doing some shunting duties.

There were quite a number of pilot and shunt duties at the Oak - the Carriage Shed and associated sidings were 55 roads wide!