Picking a date for May

I sent out a feeler email to 8 couples to see if they would be free on May 15th for dinner. For the first time ever NO ONE will be free. There is a ward father/son campout that night so half the families will be involved in that, 2 families have guests that weekend, one family is in the process of moving to Utah and will be gone by then, and the last family will be celebrating a family members birthday. We are getting down to the last couples who have not been to our home for dinner. So I really want those couples to be able to come. The following weekend is Memorial Day weekend and many will be out of town. I may have to bump it to the following weekend or the first weekend of June.
I can't believe that by mid summer we will be ready to start over reinviting couples who have already been here for dinner.