i got a response from the Biological Records Managers of MarLIN and DASSH in Plymouth
Heres what the experts had to say:
'We have looked carefully at the images and I’m afraid we can’t be sure of the identification. On the basis of the features we can see, such as pigmentation, the specimens are
Eurydice pulchra but to be sure we would need to look at coxal plates 6 and 7. In E.p. the plates are extended posteriorly, but not in
Eurydice affinis. There is a diagram of this in our seashore guide (3rd ed p. 322). The species occur in mixed populations (and E.a has been recorded in Ireland) so one has to be careful to examine all individuals.'
they were well happy with the quality of the pictures though

and they posted them up on their Facebook Sealife Survey page
sealice indeed