Ruth,
As far as dress is concerned, I would expect that this cruise will follow the standard Princess policy of casual attire during the day and a mix of casual, semiformal, and formal evenings. According to the edition of Princess's "Cruise Answerbook" that I received for my last cruise, the normal breakdown on a 19-day cruise is 8-9 casual evenings, 6-7 semiformal evenings, and 4 formal evenings. Nonetheless, the same cruise answerbook says that there are only 2 formal evenings and 2-3 semiformal evenings on cruises of ten to thirteen days, yet we had three formal evenings on a twelve-day cruise aboard MV Grand Princess last year and again on a ten-day cruise ending a month ago aboard MV Sun Princess. Thus, on a nineteen-day itinerary, I would expect at least four formal nights and have a plan in place in case of a fifth formal night and perhaps even a sixth formal night. The actual number of formal, semiformal, and casual evenings will appear on your cruise ticket.