Just a heads up to hosts to be very careful when cancelling booking(s) due to 'extenuating circumstances'. After going through a few minor hoops, a customer support rep cancelled a reservation I had for 11/30 as my partner is undergoing major surgery. Once the cancellation was confirmed, I assumed it was all taken care of. A few days later I got an Booking request for the same dates I had cancelled. It appears the rep cancelled the reservation, but left my dates open to be booked again. Fortunately I had turned off 'Instant Booking' or I would have had another booking for the dates I had just cancelled.
Therefore, I recommend that any host that uses customer support to cancel any reservation of any kind ALWAYS go back to double-check and make sure that your dates are still cancelled. Also, if you have multiple listings, make sure you cancel those same dates on your primary listing to prevent a sync from opening up the dates again on all associated listings. On a positive note, the rep made it as easy as possible on me when I cancelled, which I greatly appreciate. However, I initially thought I was receiving all of the penalties associated with a cancellation (loss of super host status, etc) due to the automated notice under the refund that highlights the many punishments infiicted on hosts for cancelling on a guest. It would be nice if that notice were not automatically generated when a host cancels for legitimate reasons, and the cancellation is in fact done by Airbnb on behalf of the host, penalty-free. But, life is not always as we wish it to be (sigh...)