Also reported on Sydenham Town Forum.

https://sydenham.org.uk/forum/viewtopic....e1ffaeee2e

Looks like it is going to be closed a while, if you need to go to Sydenham Hill via Cox's Walk use Lapsewood Walk. After crossing the bridge, take a left though the barrier follow the footpath and first right up the hill across the grass passing the flats and you will come out by Sydenham Rise.