PA Rally/Picnic Camping head count

>From the looks, we're looking at the 0-20 group. I
guess it would be smart to get an idea of the number
of days. I'm looking at coming up on a Friday
afternoon and leaving on a Sunday afternoon. I think
the 5th is on a Sat....correct?
Also...the website for the park and info is: 
http://www.dcnr.state.pa.us/stateparks/parks/l-lake.htm

It gives the group prices, individual prices etc. I
called the 888 number to get some more info on the
park...I'm hoping to see some pictures...but I've
heard nothing but good things from those on the list
that have been there.

Dan