Originally Posted by
DYKWIA
If you book economy, then you can upgrade the UK to DXB flights to business class for 39K points if you book a flex fare. So, you'd have to buy 4k of points.
Or if it's <$160 difference to buy Flex Plus (you'd have to buy it for the entire outbound to AUS) rather do that and upgrade for 30k miles (to buy 4k miles = $160). You'll earn more miles and have a handful left over for roughly the same cost in the end, but that such a long sector will be <$160 difference is unlikely.