There were a few brief bryological distractions:
Rhytidiadelphus subpinnatus by the path down to Henrhyd Falls - first found here by Graham
An intriguingly appressed Plagiochila-like liverwort on the rockface behind the waterfall;
I hoped it might be Pedinophyllum interruptum but the leaf insertion was wrong. However...
The leaf axils of the Plagiochila held a spherical translucent fungus, which isn't Epibryon plagiochilae -very odd!
Isothecium-like Eurhynchiastrum striatulum on wooded limestone pavement at Allt Rhongyr
Tortula subulata (poor pic, sorry) at Allt Rhongyr;
there was also some Anomobryum concinnatum and Reboulia here