The tiebreaker is based on the combined point total of the two teams playing in the last game listed on the weekly pick sheet. This is not necessarily the last game chronologically played, but rather the final game shown on the list of games to pick for that week.
If game times change, the tiebreaker remains tied to the last listed matchup, regardless of kickoff time.
If you have further questions or need help configuring your pool, feel free to reach out to support@runyourpool.com.