The September 18 date concluding was on the email received by the other poster; I don't see it addressed as such on rec.gov.Many Glacier Campground closed to tent and any soft-siding camping equipment effective immediately. This is due to a bear incident in the campground. NO sleeping in tents or hammocks. RVs, Motorhomes, Trailers, Hard-sided Pop-ups are allowed. Camper vehicles such as VW buses and pickup trucks with small canvas pop-ups are allowed as long as the canvas is not exposed.
Edit: I changed the topic in response to post below. I don't recall any previous season-long hard-sided-only rule in response to bear frequenting.