I don't believe that being a transfer passenger reduces your chances, or improves them either for that matter. I managed to score an gate op-up last weekend at LGW after checking in online and collecting my BP's at a SSCI kiosk at EDI (moments before we met in the EDI Terraces). Complete fluke but hey, thats the way it goes
Wouldn't do any harm asking the lounge agent about the possibility of alternative seats though.
Have a great trip and remember: you are eminently SFU

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