those flights aren't operated by UL, so I'm not so surprised.
It's a little hard to see where the cash-back is applied. Checking tickets ex CMB it only seems to give the standard fare. I don't know how or where they arrange to refund the balance (I only went as far as the passenger details page).
However - what was interesting was that regular fares (not eligible for discount as not departing CMB) are coming in at AUD2100 return in business from SIN to CDG. Good value for OW.
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