I currently have about 60,000 Asia Miles that I have been saving. However, with the devaluation coming up in the fall, I fear they won't go as far as they used to!

I'm wondering what the best use of these miles for me would be. I am based in Vancouver (YVR). So far, I am eyeing these options:

1) Travel YVR-LHR in BA J.
2) Upgrade YVR-HKG-BKK from Y to J.
3) Upgrade 2 x YVR-JFK as per new award chart.

Any other suggestions?

How far in advance do I need to book in order to secure J-class availability?

Thanks.