Way back in April I purchased one of the $328 US-Singapore round trip fares on JAL for a trip in January 2018, gambling that at that price I'd be able to get the time off work. Sadly due to work and other personal reasons it's not going to happen for sure.

If I know that, is there any reason I should notify JAL now? Based on my reading of this forum, it would seem advantageous to wait until the last minute on the small chance that there is a significant service change or some weather event that forces them to cancel/significantly reschedule the flight, which would presumably allow me to call and get some kind of credit for something due to the major schedule change. (This seems highly unlikely, but you never know!)

I have no expectations on getting my money back as it was a nonrefundable fare and I gambled in April 2017 that it would work for January 2018 (oh well!) but I just want to make sure there's nothing I haven't thought of.