As Barney boy says the boat leaves from the Old Town harbour. We took it last time we were there but I can’t remember how often the boats were. It was a nice boat ride and we really liked Cavtat.
In the past they have had a couple of places where you could book. The second one has been in a variety of places, such as Discoveries Bar, The Den etc. On our last couple of cruises there was only the one.
The most detailed description is accessible through your account. Click on Upcoming Cruises, then on Manage My Reservation, then scroll down to Excursions, click on the Paper/pencil icon. Click on the Available tab, then for each Excursion click on Details on the right.
Sorry about that, obviously I included the wrong link. Here’s the right one https://docs.google.com/spreadsheets/d/1pEoojQ5-EPmD4cI3gw1dVcYfYTXfZePdDXxU09l0H3M/edit
Definitely ring up to apply FCC to a booking. You should have had a communication from Azamara saying how much FCC you have. I don’t know how to see it on your account.
It does say that the upgrade doesn’t happen if you don’t complete the payment, so that’s always an option.
Under the old system there was no phone call and no option not to pay. If your bid was successful you just got an email telling you and the money was taken from the card you entered in your bid.