I must admit, this is my first booking with Avios, but I've been booking FF rewards for a while and I can't recall 2 OW segments costing less than a RT. In this case, for 2 pax, it's almost $280 less expensive.
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YVR-LHR-YVR = $1180.51
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YVR LHR = $478.91
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LHR YVR = $561.71
Total OW segments = $1,040.62
Total Round-trip = $1,180.51
Savings = $139.89 per person
Is this normal?