Cowboy cleaning contractor GBM have withdrawn night cleaners from stations on the Barkingside, Buckhurst Hill and Greenford groups.
While the cleaners' union(s) need to be fighting over this issue, station staff can help too. If your station has an overnight build-up of rubbish, or a spillage, that makes it unsafe to open in the morning, then don't open it. Keep either the whole station, or at least the affected part, closed, report it to the FRC, and don't open until they clean up.
The penalties ot the contract will soon make them re-think. And hopefully, LUL and/or the Infracos will re-think contracting-out cleaning services altogether and bring them back in-house.