In December I’m flying JQ from MEL-SYD on a cheap JQ flight leaving from the international terminal after I’ve enjoyed brekkie in the First Lounge. I’m then meeting a friend in the SYD First Lounge for lunch, and then we’re both flying to MEL on another cheap JQ flight from the international terminal.
Don't hope too much to it, its not unknown for an equipment swap to happen, and you will get put onto a JQd a320.
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Also, maybe you do not know, MEL and SYD int terminals, their arr and dep are on different tiers, ie, not on the same level, or storey.
You have to go into and out of Aust immi zones, so, one of the JQi flights, might get swapped, and you will be relegated to dep from T4 in MEL/T2 in SYD.
All those tag flights, are not a cert, and not daily.
To get to int dep, you have to show photo id each time you enter, the T1 at MEL for a dom pax on an int flight, and then in SYD, go out into the public area, and then back into T1 outgoing immi, not to mention, having to go through int sec screeninbg, which can be a pain in the you know where.
To get from int arr to int dep, you have to have a true transit, and a BP, so its most likely, you have to be immi incoming cleared to enter Aust, at T1 int arr, and then go out into the public area, and then back through immi outgoing, and int sec screening at T1.
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Have done it several times, with JQi SYD - MEL, and QFi BNE - SYD, not at the same time, not on the same, day...
Would I do it again, maybe, but I wouldn't do it too many times on the same day!