Doubt that AA miles or instruments can be used to upgrade a Cathay Pacific flight. Their business class is a pretty comfortable ride (did SFO to HKG about a month ago), enough so that I wouldn't spend much to upgrade. Service was excellent and managed to sleep a fair amount.

They have an unusual (to me) bidding system for upgrades that may be of interest.

Happy travels!

https://upgrade.cathaypacific.com/of...fic?lang=en_HK

How it works

Step 1: Check your flight eligibility

Upgrade Bid is available on selected routes – verify your flight eligibility by providing your booking information in the panel below.

Step 2: Place a bid to move one cabin class higher

You'll see the strength of your offer while bidding. If successful, you’ll be charged your bid amount and receive confirmation two to three days before departure.

Step 3: Enjoy your upgrade

Once your upgrade is confirmed, you’ll enjoy the many benefits of travelling in our award-winning Business Class or Premium Economy. Please note that extra baggage allowance will not be included in your upgrade.