I see two cruise ships in port in Dubrovnik Sep 1st, but they are small enough not to be a big issue. http://195.29.106.30/

If that's your preference, fine, but no need to join a tour -- bus from Split to Skradin, boat or walk to the park entrance, visit the park, reverse.

You did a good job checking the cruise ship schedule! Cruise passengers leave Dubrovnik old town 1 hour before departure of the ship leaving you plenty of time for sightseeing. Trip to Kotor is a great option but check cruise ship schedule for Kotor too. Here you can find out some useful tips for your Montenegro trip. For your island hopping I recommend Korcula and than Hvar (both on the way to Split with the same ferry connection). Even though Split is much bigger than Dubrovnik, it is better to spend more days in Dubrovnik than Split. One day is enough for sightseeing of Split city centre (Diocletian's Palace) the rest of the city can be interesting just in case you would like to explore modernist architecture from socialist period. For your last night I suggest you stay in Cavtat. It is a charming coastal town around 5km from Dubrovnik airport.

Might I ask what links you're using to confirm cruise ship schedules for Dubrovnik and Spit? Thx,

Hi,

I used the below links for the cruise schedules.

Dubrovnik, Croatia Cruise Ships Schedule 2019 | Crew Center

Split, Croatia Cruise Ship Schedule 2019 | Crew Center

Thanks for the reply. We have decided to spend more time in the Split area than in Dubrovnik.

Thanks for the info. We are going to spend some additional time around the Split area. Looking forward to going to Plitvice Lakes National Park.