Originally Posted by AAway

It doesn't matter which airline you book through, as long as your AA# is associated with the booking.
Just be sure not to book an "X" fare, as these are not upgradable (not even to a "premium") seat. AS's Premium Cabin is equivalent to AA's MCE seats and AA allows you to book these seats for free based on your status regardless of fare class, whereas AS does not - so it's important to understand that distinction.
When you complete your booking, you should be able return to the booking and select a Premium class seat for free. Once you're in a premium seat with no extra charge, you can be reasonably assured everything is happening as it should be, as far as AS recognizing your elite status. You should see "first class waitlisted" or something to that affect on your booking once you're in a premium seat.
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