I have been looking again at the platforms and have noticed a glaring error on the facing, I have made it stone all the way around, as it was in it's original guise. Further digging and picture checking has revealed that it should be brick from 2/3rds the way down the main platform right around to the engine shed. This was done during the re building work of 1916 when the bay platform was added, and I had missed it when building my platforms.
To sort this out I decided the easiest way would be to use scale scenes brick paper, laid over the plasti card. This will have to wait until it's painted. I am hoping for a days modelling this week so will be looking to add some pictures shortly.