1) VS codeshares with SQ on their flights to Australia but that's not important for you to claim your miles if your flights are booked through SQ and carry SQ flight numbers. You will be able to earn miles and tier points on SQ flights.

2) You can add your Flying Club number when you check-in online or call reservations in advance. You can also check your booking at anytime on the SQ site by clicking on "My Bookings" and entering your SQ PNR (Passenger Name Record).

No problems with using the LHR Clubhouse on an SQ business class ticket. Revivals lounge access is only for passengers booked in Suites on the SQ321 arrival. No access for business pax.

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