Wait! You are right I forgot. I am using award tickets in December. I believe I should already qualify. I had totally forgotten that point.
As long as the Award Tickets are on DL Metal with DL flight numbers, booked with DL Skymiles.
To your other point, yes I should check all of it carefully for any surprises.
Yes - check the changes to GUCs though for SYD it may not matter much (or even be better). GUCs didn't often clear in advance to SYD and often didn't even clear at the gate because flights to SYD went out full with paid fares in J. But with the new rules, you could buy Main Cabin and at least gain an "Instant Upgrade" to Premium Select which x4 to SYD is worth more than the $1100 MQDs you're currently short of DM status by. And you would at least be standing by for an upgrade to D1 beginning at T-24 hours for the flight to SYD and could get lucky at the gate.