My minimum stay is 30 days, and airbnb automatically imposes a policy that if they stay less than 30 days the balance of the month is not refundable. The rare time in the past when I’ve approved a change of reservation in that situation, air has assumed I would keep the balance of the money.
This time, they offered me the option to keep or refund the difference, suggesting that most hosts refund it.
In this case I refunded it because the guests left the room spotless and even washed the sheets and remade the bed, saving me lots of arthritic agony.
From a financial point of view I preferred it when I wasn’t offered a choice.
This seems to support the idea that air is veering off in the direction of favoring guests over hosts more and more.