Those monuments that are normally considered ritual /ceremonial e.g. cursus , henge etc. are not often found in upland situations or particularly associated with springs . Springs are more common in upland areas and consequently are less likely to be noted valued and considered sacred as their cousins on lower ground ,there is also the problem of who decides and what is the criteria for any of these mulitifarious springs being designated “sacred “ .
In the upland areas the most common monuments , apart from hut circles , are likely to have a funerary context e.g. various types of cairns . Which is exactly what we find with the monument investigated by Darvill and Wainwright . My concern is how they have turned a typical upland cairn in an an area where springs are common and unlikely to have the sacred cache of their lowland counterparts into a ceremonial monument ,henge was specified , this is not only only unlikely but another convenient connection to the their main purpose i.e. associating it with a monument with a similar name in Wiltshire but the “sacred “ local springs provide yet another association with their desperate Stonehenge = hospital model . We will have to wait and see what their ceremonial monument actually is but my guess is that the cairn has a ditch and outer bank a common enough feature but that does not make it a henge. Whatever the evidence for burial /deposition they will become the architect of Stonehenge or the Eddie Stobart of Preseli with their burial site looking towards their creation/ scene of greatest mobilisation of man power until Dunkirk .
Standing stones are a feature of the lower ground around hills with a small group around the 300m contour at Waun Mawn ,any standing stones in the area would have been recorded long ago and considering Toby Driver recorded the actual monument he certainly would have noticed if there were any standing stones present .Another tenuous link with Stonehenge but there is the intriguing possibility that the putative “standing stones” are not even bluestones as this would have been trumpeted . This is not interpretative archaeology anymore , it's not even Bernard Cornwall it's more like media and fund driven fantasy .