I am interested but my schedule is inconsistent / can change any given week but I can say that I work Sunday's no matter what and should have Saturday's off except for next week. So I should be able to make a Saturday right. The dates you have listed aren't right... July 9th is a Monday / July 10th is a Tuesday.
To get more interested you could check out the Northeast Slingshot Group on Facebook. This area here doesn't seem to have a big local following
If it rains on the scheduled date, it will be on the next Saturday and if so I hope you can join us!