Reinvite?

Brian and Amy need to be reinvited to join, I think. They clicked it once to see what it was but were busy or something so they didn't sign up. But now when they try it won't work - it says something about being good for one time only. I don't know how to do that (or if it is possible for me to do it), so here are their e-mails: Brian is bkbake at gmail.com. Amy is amding at gmail.com.

Also, is there a way to change the default time & date? It always comes up as Pacific time, and I think most of us are in EST.