I think it will depend on the grit you dull it to. The more course the grit, then the longer it will last. I would not expect it to last much more than 15-20 games before you will need to re-sand it.
I only took mine down to 600, but it would only last 3 league nights, then need re hit. The amount of oil on the lanes is going to matter most. I wipe the ball off every frame, that helps, but you will not get much more than that.
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