CBLintonAnd you did it very well, too, if the pictures are to be believed!!
There are a number of
beach threads (of which this is one) - IIUC, you have to ensure that you get PPR from the owner, research the tidal state and the condition of the ground then just do it!
Good point from GtE regarding ownership below the HWM.
[Edited to note concurrent posting with Geng the Eng]