We've watched ships leave Port Canaveral before. It can by almost like a convoy, but then somebody will be waiting for someone and break things up. I believe their must be minimum cliearance they try to maintain.
Last year we sailed in a small armada with ships from Carnival, Royal & Celebrity from Cabo San Lucas to Long Beach.
All I ask is a tall ship and a star to steer her by; John Masefield
Carnival: Glory 2004, Destiny 2008, Splendor 2009, Freedom 2011, Valor 2012, Dream 2013
Celebrity: Summit 2011
Princess: Ruby 2010, 2014, Caribbean 2013, Coral 2014, Regal 2014, 2016
Sail Windjammer: Mandalay 2017
Star Clippers: Royal Clipper 2015
Carnival Liberty New Year's Eve 2007
Liberty of the Seas 5/2008+11/2009
Allure 1/16/ 2011
Vision OTS 2-14-2015
Freedom OTS 3/6/16
We have sailed out of San Juan three times when there were four ships, CCL, NCL, RCL and Princess embarking thirty minutes apart. It was fun to watch them sailing while waiting your turn. One time we were to have been first but the cpatain announced that we had some folks delayed at the airport so we waited for them and went third or fourth. We were sailing late in the evening (first ship to leave at 10 pm) under a full moon so it was quite a sight. [big sigh]