Welcome to Cruise Critic, it looks you have already received good advice about the coach transfers.
If you want to chat with other cruisers on your sailing that's best done on a roll call. Your dates cover several different itineraries but this is the thread for the final section.
You can also ask on the British Isles board here
https://boards.cruisecritic.com/forum/148-british-isleswestern-europe/
I agree with the other posters, a surprise is too risky.
What date are they arriving? It's always worth checking her actual ETA the day before, she was 4 hours late into New York this week.
It's good to hear that tendering worked well, some of the reports from the British Isles cruise weren't very complimentary.
How lovely to be able to stay on board.