Originally Posted by sdsearch

Because there's only zero to a few international travelers looking for such tickets (at those times), while there are zillions of domestic travelers looking for the domestic portion (at those times).

So to the international flying public at this time, making one seat available is "good availability", while to the domestic flying public, making only one seat available (which is immediately snatched up by someone else) is still "bad availability".

(Availability at anytime amounts is always there, as long as there is a seat available on the flight, so it's misleading -- for purposes of anyalysis, anyway -- to say that "the number of miles needed is different".)

What's going on in this case is that there is saver availability for international flyer, while there is no saver availablity for the domestic flyer. The anytime avialabilty is there in both cases, just not necessarily needed in the international case.