Hi there, Rod,
Thank you very much for your explanation.
I remember the time when the four companies were nationalised at midnight – the bit I can't remember is whether that was before or after 1949.
Do you know if any steam locos were built (or completed) after nationalisation? If so, would numbering have continued to be controlled by the relevant loco works, e.g Derby, Didcot, Eastleigh et alia?
Thanks again and best regards,
Swarf, Mostly.