I believe it to be 6mo.
you can reserve campsites 9 months in advance
This park is run by the US Army Corps of Engineers. The website for information is https://www.nws.usace.army.mil/Missions/Civil-Works/Locks-and-Dams/Albeni-Falls-Dam/Project-Recreation/. The phone number for reservations is 1-877-444-6777. The website for reservations is www.recreation.gov. In the past they've taken reservations up to nine months in advance. They also have a waiting list, by phone. This campground fills very early.
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