FWIW, My partner was booked on JL003 in J on March 25, using an AA award. (I am in JL005 two days earlier, no date had 2 award seats). For no reason other than I was a bit bored and looking at lounge access in JFK, I tried to retrieve his reservation with no luck. After reading this discussion I substituted JL005 for JL003 with the same PNR, and 'presto', up came his reservation. He swears he never got an email about the change (but how could he tell with the barrage of daily emails exhorting him to buy more clothes for which we have no closet space, but I digress).

Anyway, the change happened seamlessly, but it does mess us up as I was going to meet him at HND and we were going to take a flight to Hiroshima on ANA, (which I can reschedule for the whopping price of sixty cents for both), but it shortens his trip by a day. In looking at the JL schedule for North America, there are currently no flights which arrive Japan in the morning from any gateway.