If you encounter new matchups throughout the season, you can add these teams to an already imported schedule. To do this, navigate to Schedules on the admin tool bar and click Edit next to your schedule.
Navigate to Step 2 of your schedule, Schedule Teams. From here you will see all allocated teams already in your schedule. You will have the option to add additional teams. If the team is external, just type in the name and click +Team. If the team is internal, you can just click the + button next to the team to allocate it.
After the new teams have been allocated, click Save Allocated Teams at the bottom of the page.
Once you have saved the new teams, you can click on Step 3 of the schedule and click +New Match. You will see the new team as an option to choose from in the drop down menu.
Just save your schedule with the new changes and you are all set!