I was there two Saturdays ago. They were not open and I see workmen sitting outside eating lunch. Check their website, it doesn't show the Portet Range site.
As far as I can tell, never. I went there a few weeks ago expecting it to be open based on the hours displayed on Google, but they were closed, with ladders propped up inside looking like they're doing renovations. Call ahead before you go and make sure someone answers the phone to confirm they're open.
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