Very interesting, ta. If you have the coordinates you could add it to the TMA database as I did with Redcar Beach Submerged Forest - as a Mesolithic Site - last year.
Bit of a haul from you, I didn't mean you going into Holmhead mode and whizzing off..just wondered if there was anything online more specific - or even the right OS map for a six digit grid ref for the bay? I've a 'thing' about submerged forests, not the only one here.