When times become unavailable: "Oops time no longer available"

There are fives stages to scheduling a participant in Ethnio:

1. Add Open Interview Spot    Any time you add to Calendar - AKA an OIS
2. Invite    You can invite unlimited people to a given OIS
3. Confirmed  Once someone is confirmed, the time disappears for other respondents
4. Completed
5. Paid (optional)

One thing to keep in mind is you can customize the "Oops Time No Longer Available" page from Scheduling >> Emails & Landing Pages >> Landing Pages, so that if you invited multiple people to a given OIS, they can still pick a new time for themselves, since you've indicated they are at least somewhat awesome by inviting them: