There's two spots that might resolve your issue. Both are in the Setup Manager.
1- In the Event Manager section of the Setup, there is Year Selection Start and End. I'm not 100% sure if this only refers to the Event Manager itself, or if the settings will also affect the TOC.
2- In the Navigation section, there's the Navigation Starts and Ends. This will actually limit the navigation to the year range you define. The calendar will block going any further.
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