What I did see however, was my only clouded yellow of 2018, typically flying at great speed at about waist/chest height. It did not alight so there was no opportunity for photography. My mind also wandered back to the 1980s when some bird-watching friends had a monarch butterfly (also in September) at this locality.
The other recent `yellow butterfly` was a male brimstone in my Pwll garden a couple of days ago.
Above: the Penrhyngwyn shingle. I must remember to check the frequent sea mayweed plants for chamomile shark caterpillars next summer.