Does the total of Nights Booked under the Earnings summary for a particular year include all nights if it's a shared calendar with another booking site?
I would expect it is the nights booked on Airbnb, creating a Airbnb reservation (wherever the booking is made from). You can test it yourself by downloading the CSV file from Transaction History "earnings from last year". And after totalizing booked nights, compare it with nights booked on the statistics page for last year.
@Rose1610 We have Airbnb bookings, private bookings and blocked dates for maintenance/holidays. The only way to keep track of all this is by spreadsheet that is updated at every check in. It is more complicated as whilst all revenue is taxable only some bookings count towards us being business rated and different bookings count towards furnished holiday let tax status.