The club CAN modify the schedule by accessing the team page from the Club Directory. However, turning it on means that the team can also make changes to the game schedule, too.
In the Season Structure Wizard you will set the TM GAME EDIT to Clubs.
Once that is setup, then the Club person can login to the Club Directory
Click on Team Administration
Click on the name of the division for that team
Click Edit Games
As a full admin user you can test it out, just login and click on Club Directory from the Elements page. Remember, the only thing is, if it's setup then the team CAN make changes if they have access to the team page.