Good route Michael - I did the 172 route yesterday as impossible to get the 171 (full).

I think you can also get the P12 from Surrey Keys - I think near the Decathlon store but can't remember.

TFL's communications were pretty poor yesterday. Got on train at Shoreditch, saying it was going to West Croydon. Then told it would terminate at New Crosss Gate due to late running. Then two stops later it was going to New Cross instead of NCG. Then get off and told no more trains past New Cross Gate.

If you are still in town, you can of course try and get a train to Crofton Park and then get the 122 or other buses up from there. Think they leave from Blackfriars but I may be wrong.