would like to set up automations related to a calendar event so that if we still have availability in the calendar, the automation will continue, and if the contact books into that calendar, they can be segmented into a new if/else branch of emails.

eg, my team would like to host in-person training sessions once per month for limited contacts. We would like to let the contact know that we have dates and times available, and they should book in asap, as spaces are limited. If the contact hasn't booked, they receive specific communications about available days and times left in that calendar. If they have booked, they are branched into a separate sequence of comms before the workflow begins again for the new month.