This was our first cruise and I was aware that some stops would be short, however if time is lost through bad weather or technical problems then stops are curtailed and sometimes you are not allowed to get off the boat at all. Apparently the schedule is the same in winter so the chances of stops being curtailed at that time must be much higher.
Excursions are expensive. We booked ours in advance. BEWARE THAT IF YOU BOOK IN ADVANCE FROM THE UK, YOU ARE LIKELY TO PAY 20-25% MORE THAN IF YOU BOOK ON BOARD. There is a slight risk that a trip may be fully booked, but when we travelled all excursions were still available the day before. My advice would be to plan which excursions you want to do and book them as soon as you can once there.
Excursions we did: