I received an auto email from AA today apologising and offering 20k miles. I was EXP on Y ticket in J cabin using VIP upgrade.

I had a much shorter diversion on PVG-ORD to LAX that ended up getting me home about the same time, not 18 hours later. They offered 10k for that. Either that was generous of 20k is a bit low.

I haven't seen (yet) separate miles for NRT-HKG segment.