Short answer is no - they will not increase your status based on future bookings. Future travel may get you over the line to retain status, but actual already made flights are necessary to increase status.
WP is the top FF level, SG is the next level down, then there is PS and finally NB - you are an NB.
And in flying, am I right in thinking that the most direct route (i.e via somewhere on the way) will get you more status credits than maybe a direct flight? If you have the time, Bne-Per via Mel would earn more SC than Bne-Per?
Correct - the SC's are based on the flight sector you are ticketted for. So if your fligh coupons - whether they be paper or electronic - read SYD-CBR-MEL-ADL you will get three lots of SC's. I actually did this in J last year for about $20 more than a direct SYD-ADL flight (taxes) and got 90 SC's instead of 30 and 3750 points instead of 1250.
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