That's wax pull up I cleaned 1 last week and have got 1 myself.
LTT sell a powder that you apply and leave on iy and it dras out the grease and the dye, but the dye can be put pack in or you can apply Grison balm layering iy on and buffing it in, colour required is London Tan for thr Grison.
Shaun
PS not sure if Ben sells anything but I believe that Judy's is vert good but takes a long time to work.