You can find most of the info from the existing thread on this topic: New status programme (launching in January 2024)

Given you think this is a fee reduction, you are one of those overseas members who didn't fly JAL enough every year to maintain your JGC for free. In short, there's no change other than lower renewal. Unless your flying pattern changes, the star grades probably won't matter much to you. You will need to earn 1500 additional LSPs for it to matter, which for the time being translates to equivalent of 300 JAL domestic flights, or 300000 international sector miles, or a combination of that.