Welcome to the Waitlist
Send this the moment someone joins your waitlist. It shows their place in line, says when invites go out, lays out the three steps to getting in, and offers a referral link to move up. Replace the position, invite day and referral rule with your own, and only promise what your launch plan can deliver.
Loops
Store the position on the contact
Save the waitlist position and referral link as contact properties when someone signs up, then trigger the workflow from that signup. Keep the position current as people move up, and remove the referral section if you do not run one. When invites go out, send a separate access email. The waitlist examples show other launch shapes.