Well at Walkden they lengthened the platform and only re-did half the platform flooring and introduced longer trains.....they have now realised their error so have had to erect a temporary extension to the platform to accommodate the longer trains so they can do the other half of the platform...I'm not sure whether that is the same situation at Swinton though.
No error - the platforms were virtually completely non-compliant for stepping (you needed a ladder at Walkden), so the new extension was built as correct as possible and now the original section is being corrected. They will be 6-car when completed.
Would the platform heights as originally constructed have been influenced by the types of Lancashire and Yorkshire Railway passenger carriage design appertaining when this through route from Windsor Bridge Junction to Crow Nest Junction that avoided Bolton was constructed ?