We chose a back to back itinerary with 7 days cruising towards Norway - 3 ports then 7 days in the Baltic. Norway was great and we had excellent weather for most of the 3 weeks.
The Baltic itinerary changed such that Stockholm was cancelled and we would now overnight in St Petersburg. At first glance this seemed really good but as we rarely use expensive ship excursions we were unable to arrange for an evening ashore nor take advantage of the second day. We were meant to be in Port until 2pm on day two but that was changed to "all on board" by 11am.
So really the 2nd day became an at sea day effectively.