Concrete Beware of Trains signs

[48218]

I came across a concrete "Beware of trains Stop Look Listen" sign on my old branch line (long since gone). Although this was on the LMS system I wonder if anyone has come across similar concrete (not iron) ones?

The sign was on the North side of the line at an occupation crossing.

Do you know of any? and when where they introduced? is it possible the L&Y put it there or was it more likely the LMS or BR?

Thanks,
Andy.

[Mickey]

Possibly introduced either around the time of 'The Great War' 1914-1918 the same time that 'concrete signal posts' appeared on the GNR and later on during the LNER between 1939-1945 and WW2 due to a shortage of timber during both wars?.