I wish they had separate phone lines for booking new reservations and for questions/issues when already booked.
I was on a cruise 2/19-2/23 and I had to call twice last week with last minute concerns. The first time I waited an hour and 5 minutes but finally got through. The second time was the night before our cruise with an urgent problem with port transportation in the morning - I waited on hold for an hour 30 minutes and then the call just disconnected. When I tried to call back a recording said they were having an issue and to try again later, but by this point it was after their stated closing time. I was pretty stressed all night not being able to speak to someone about a very time sensitive issue for an existing cruise booking because the lines are so tied up with everyone booking new itineraries.