Complex dynamic pricing models are employed by airlines which determine the un-sold flights about 72 hours prior to departure. In an attempt to eliminate fuel costs, these systems automatically reduce remaining seats, which results in a window known as distressed inventory. This can be used by spontaneous travelers, who can use Search Everywhere functions on aggregators, which rank price over destination. Last minute trip deals to anywhere usually involve loss of flexibility in departure time like taking the first flight of the morning. https://askforairlines.com/blog/last-minute-trip-deals-to-anywhere/