I actually asked this to the guy mowing the lawn there today. It’s to let the field rest & regrow the grass. Like a baseball field, you have to let the ground mess otherwise it gets torn up & becomes a muddy yucky mess.
I don't know if anyone knows for sure. We started going a year ago and only one side at a time has been open. I assumed it was to give the ground time to recoup. Maybe ask on the FB page.
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