Thanks, I was able to see availability following these directions:
https://faq-en.jal.co.jp/app/answers...the-upgradable
I did call before I booked to verify and the availability for several flights matched exactly what I saw.
Went ahead and booked online the K fare and then did the upgrade online as well for 30K miles transferred within a few minutes from BILT
A better flight opened up looking for X space on itamatrix and called and they moved me to that flight no issues