We have a lot of members in our organization. And each member belongs to a separate "Chapter" within our group. From time to time we send to ALL the Chapters using the main Mailchimp List. But our Chapter leaders have the ability to send to their specific Chapter using MailChimp Groups.
So when using Mailchimp we would like the ability to select which Mailchimp Group we want to receive emails from regarding the calendar. See the attached screen shot to show the mailchimp form on our Web site. A person gets on the list then decides what Chapter (Mailchimp Group) they want to receive emails from the main list.
Then we can target Calendar events with a specific group in Mailchimp.