Will be flying from WAS to TYO in the next few months and curious if the experts had any wisdom as to which leg USA to TYO might have the best history of SWU availability? I could obviously do anything since will be flying from east to west. (Lots of seats open but nothing can be cleared now.) My thought process:

JFK:
Pro-- Anyone looking to pay cash for J would presumably choose JAL over AA. Folks originating west of the east coast would likely choose DFW or LAX to avoid flying east before west.
Con-- Presumably lots of high spend individuals might buy the last J seats close to departure.

DFW:
Pro-- Two flights to TYO (i.e. HND and NRT), but of course would have to book one or the other in advance
Con-- Lots of high-LP EXP's might take any SWU spots.

LAX:
Pro-- Anyone looking to pay cash for J would presumably choose JAL over AA (and could do so also from SAN, SFO or SEA).
Con-- Folks flying AA originating between west coast and midwest would likely choose LAX to avoid flying east before west.

Anything I'm missing / other insights? Of course have alerts on ExpertFlyer for all of these...

Thank you!