We did this "port" which is really Dover on our own in the listed city of London. If you were on the ship you would have had to travel back to London either on your own via train or via planned excursions or offered bus from the ship. London is great, but not doing it from Dover with the loss of 2-3 hours for travel. We requested an 'embarkation deviation' and spent the first ship night in London (at our exepense) and joined the ship on day 2 before actual departure from Dover. Allowing us a day and 1/2 to see London.
Visited: Aug 25, 2017