Are there any weekend days people sometimes cancel on and become available if you're already camping there on a weekday?

There's the little hut you can call. During the day someone is generally there.

yes, people cancel.. for best options, call the campsite directly ☎️

Yes, I would just call

We use a reservation service that has live access to that info. Visit the reservation section of the website www.parks.state.wa.us for the live availability. If you see a site is suddenly available go into the campground welcome center and purchase the site. The campground does not get notified when sites are canceled and they cannot hold sites. Occasionally people need to cancel but it is random. At Twin Harbors most people depart on Sunday and Monday if that helps. Good luck and thank you for choosing Washington State Parks.

Yes go on the beach if you don't find a ranger in the park you will find one on the Beach