Scheduling Groups of People
I have found that instead by far the best way to set a date, for groups of say six or smaller, is for the person with the tightest schedule to send out a comprehensive list of all the dates that they are available during the possible time span, someone else in the group to edit that list down to just the dates that they are also free and reposts, and so on, until, when the last person posts, and you are left with a comprehensive winnowed-down list of date that all people are free.