Help with booklet

[the raven]

I have come across a small booklet  with the title UK port and staff travel 1939-1945 on the inside is a list of names and addresses of various people from all over Britain and a few overseas ones and at the back of the booklet is a list of areas of the UK and the names of people for that area ..reason I'm asking in this form is that my grandfather is named in it and during ww2 he was with the intelgence corps based in Holyhead  and I assume it something to do with that ..

[Crumblie]

It would not make sense for it to have something to do with the Intelligence Corps because if it fell into the wrong hands it would be a very big security problem, I would also expect it to have a security classification but it does not appear to have one.

[the raven]

That's what I thought ...part of his duties at Holyhead port was watching  passenger movements between  Holyhead and Ireland