Yes, our trip in September was on Oceania. Actually, it was probably similar to yours, but in the opposite direction. We sailed from Dover to Barcelona.
We arrived a few days early. Took the train to Brighton directly from the airport. Spent the night there and picked up a car the next day and drove to Dover, visiting Leeds Castle on the way. The next day we went to Canturbury and drove around the area. Had a lovely lunch on the back deck of a restaurant at St. Margaret's Bay, with views of the cliffs and the ferries going back and forth to France. The next day, we did some shopping in Dover and then went up to the castle before going to the ship. My husband dropped me off with the luggage and was going to return the rental car and take a cab back, but one of the guys at the dock followed him and brought him back in his truck. Talk about service. They got a big tip!
Thanks for the web site info. Stay in touch.