Why not? Your example is particularly relevant because precisely, the whole bucket availability strategy of full service airlines is precisely based on projection. Today, only 20 seats may have been effectively sold on the flight I want to book and the availability may well show O0 N0. In one week, the airline may well have sold 40 seats and now the availability will show 09 N9. The entire airline business is about evaluating capacity at the time it matters based on information available and how they compare with known trends up to several months before that time.

And on a more 'technical' note, it seems clear to me that airlines have complete discretion to evaluate whether they have the potential to accommodate the guests that they have the option to accept or not on a capacity-basis.