@Aunt-Betty0, you already can easily override your minimum stay requirement on a per-date basis. When your calendar is showing, click on Availability Settings near the upper right. Scroll down, and near the bottom, just above the Sync Calendars line, you'll see a link saying "Add another requirement". Clock that and define away! You can use that to set longer or shorter minimums by seasons, or for specific dates, or for weekend stays.
To set a specific day back to a 1-day minimum, select Specific Dates and when the start/end fields appear, enter your start date (the day you want to make available). The end date will default to the following day.
Be aware that there's currently a bug in this process, which might or might not surface for you. If you're opening up a single "orphan" day that was originally the subject of this post, you won't be affected by the bug. But if you're changing a single day's minimum requirement and that day is followed by another currently open day, the change will also affect that following day. In other words, it will also now have a 1-day minimun requirement. This bug has been reported to AirBnB, so I hope they'll fix it soon, if not already.
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