At the start of each subscription term, your account will default to the School Pool option. Once you've been invited and registered, you'll be able to log into your account to add teachers and set limits from the Roster Management page:
https://www.tptschoolaccess.com/roster-management
If you’d like to allocate resources at the beginning of the subscription, we recommend you do it as soon as your roster is updated. Setting limits as soon as possible will allow teachers to see their allocated licenses at the beginning of the subscription term.