Minor problem with the layout name ! 70A is of course the Nine Elms LSWR sheds BR era code, which was located alongside the LSWR mainline in Wandsworth. But "around Battersea" implies the LB&SCR shed. Further complicated by the fact that the ex SE&CR shed at Stewarts Lane is also in Battersea. While you could shuffle back & forth between Battersea shed & Stewarts Lane sheds as they were only a few hundred yards apart and directly connected. It wasn't possible to go between these sheds and Nine Elms shed. Unless you went via the West London lines to Clapham Junction, and then reversed up the South Western mainline towards Waterloo !! Nine Elms shed is today the site of New Covent Garden vegetable market. Happy Modelling !