When you are playing Madden 21, the playbooks you use throughout the year will see updates based on how the team is playing in real life.
When in Play Now and Franchise, the playbook for specific teams will update based on new schemes and new plays during the real NFL season.
It's not clear how quickly these will update, but we wouldn't be shocked to see weekly updates to the playbooks. This does not appear to impact your playbook in Ultimate Team.
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