As an example:
Let's assume you have a booking from 7th - 14th July, another from the 21st July to 28th July and operate a 3 night minimum stay.
When a potential guest views your main availability calendar it shows the 19th and 20th as unavailable as well. Now if that guest is trying to make a full week booking then they will pass your property by.
In the unlikely event that they go ahead and try to book their dates anyway and select a start date in the 'pop up' calendar this still shows the 19th and 20th as unavailable, which magnifies the issue. If however they still persist with trying to book the 7 nights and click on the end date miraculously the 19th and 20th become available.
So Airbnb you need to address the issue with how the main availability calendar is initially loaded and either NOT show minimum stay nights, such as 19th and 20th above, greyed out or introduce some colour coding.
Rgs
Ian