I had a nice reply back from the Warden at Skokholm Island regarding the GBB me and Pete saw at Padstow on friday :
Thanks for this record Bob.
W:140 (HT94995) was ringed as an adult female on 18/5/16 here on Skokholm Island. She bred successfully this year but has not been seen since.
The majority of our adult birds stay locally, so this is a slightly more unusual record (only three adults have been seen away from Pembs, all in Cornwall). However over 25% of our juveniles are seen in Cornwall. The 2015 seabird report giving more details of this project is free to download here:
Thanks for the record and all the best