We're there yearly - check in is posted at 3pm but they start about 2pm - this year the check in line on Sunday was taking so long those of us with guaranteed sites ($25 extra) were told to go set up camp & stop back by to check in before 730pm which was great! Reservations are paid for fully when made & they dont take any payments in office after 8pm for add ons. I think no Saturday is for summertime only. Check out time is a firm 12noon - they used to let you buy a late check out for 2pm but had to end that a couple summers ago, but could be available in the "off" season still.
No check ins on Saturdays, i believe. Also, ck in is 11 or 12. But, if you arrive early... They may let you ck in early if site has been cleaned up by maintenance. At least this has been the case for us in the past.
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