Calling JAL is most accurate way.
However, basically, IMHO, if business class award is available at basic miles (50000miles), probably upgrade award is available.
For 17Feb, JFK-HND requires 101,000 miles (5 seats remain)
For 21Feb, HND-JFK requires 50,000 miles (lowest basic miles, 2 seats remain).
So, you have good chance of HND-JFK flight upgrade.