I'm having an issue whereby I've 'block booked' out a month and then I get a pre approved reservation in that month. The issue I have is that if I keep cancelling on potential guests, that I will go down the rankings.
There are many threads here in the forums that discuss this exact issue. You need to contact Airbnb to have them cancel without penalty if the dates have opened up spontaneously. Airbnb will be able to look at the data and activity history to see what has happened.