I'm on an award ticket in Y on NRT-JFK (JL4). The flight is in 18 days. There are 9/38 J seats remaining. The NRT-JFK leg is part of a larger itinerary from CMB to JFK; does anyone have any anecdotal experience if there is decent chance at T-20 for some of these 9 remaining J seats to become available? I read that JAL releases seats at 10 AM Japan time/8 PM EST; does that apply to partner awards?

Wondering if I should switch my itinerary to CX...but I'd rather go via Tokyo (and have the day to explore and eat).