Hi Pojung, welcome aboard!
When your ship pulls into each port of call, there will be plenty of time to explore all that the port has to offer, including Port Adventures you might book through Disney Cruise Line. If the port is one where the ship pulls right up to the dock, as most are, you are welcome to come and go throughout the day as you please. In your Personal Navigator schedule of events, or on the
Disney Cruise Line Navigator App once you arrive on the ship, you'll see a listing of the all ashore and all aboard times for each port. As soon as the ship is cleared for debarkation in the port, an announcement will be made, and guests will be directed as to which doors to use.
If you book one of the amazing
Port Adventures, you'll most likely be meeting your group onboard the ship to check in with your guide and then walk off together. But, if you're heading out on your own, just leave whenever you'd like and return whenever you're ready!
In ports of call that require the ship to drop anchor out in the port, you'll be using tender boats to go to and from the dock. In this case, instructions are given as to where to meet if you're heading off on your own, and you'll be then guided to the next boat. Port Adventures groups will also meet onboard, and take a tender boat together to shore.
I do recommend that you plan to be back to the ship plenty of time before the all aboard time. That listed time means that's when you absolutely must be back onboard, so don't wait until then. Especially in tender ports, there can be a longer line on the dock to wait for the tender boats, so you don't want to run late and find yourself missing the boat. But, honestly, Pojung, just plan ahead for your return time and you'll be all set!
Have fun!
Marcy