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I would start by using another airline's website to search for award space. Neither AA nor AS requires a log-in to search for award space. A quick search on the AA app shows some early December dates with two-stop availability in Economy only from YVR to PNH, but it utilizes both JL and QR on the itinerary. This would trigger BA's multi-carrier redemption rate, unless you were to book each leg separately (perhaps stopping over for a day or two en route?)

If searching on AA just for YVR-TYO, any itinerary involving JL will price at exactly 35,000 miles. Any date showing a higher redemption rate would be for connecting travel on AA, so ignore those dates.