As a league administrator you can lock previous seasons and alter which season you would like to be the default season.
To lock or unlock a season click on the edit button next to that year (the three blue dots mean those seasons are integrated with Whole Game and cannot be deleted as the seasons are archived).
Below you can see a list of options including how to hide a season from the public page and how to lock or unlock.
Unlocking a season will then give you the option to make it the default season, meaning when you load Full Time, the page will automatically open on that season.