@Eddie-And-Michelle1 We have had this happen too. I informed the guests that were due to stay straight away and offered them a choice of the following.
1. A change of dates if they would prefer that.
2. A full refund and I would contact Airbnb about it to try and get the fees refunded too.
As it turned out they weren't in the slightest bit bothered and decided that they would go out for breakfast on that day and spend the rest of the day exploring the area.
So communicate as soon as you can and see what they come back with.