Fleets Page
The Fleets Page gives you an overview of all the missions you are running as well as their return times. It also lists how many fleet slots you have available and how many are in use, as well as if you have Hired the Admiral for a +1 fleet bonus (found in the Store)
Each fleet listed displays the amount of time left until a particular leg of the journey is completed.
The Type field describes what that fleet is doing.
Origin and Destination show the coordinates that the fleet is flying from and to.
After that is a breakdown of what ships are in your fleet.
Finally, in the Actions column are commands that you can send to a fleet on a mission. If the fleet is returning or deploying then you cannot alter its course. However, if a fleet has not yet finished its first leg of a mission you can recall that fleet and it will return to its origin coordinates. If you have launched an attack you can select Formation and ask your allies or buddies to join in on the assault.