I would guess that each flight segment in any itinerary is booked in a separate class of service (which may be the same or different), and accounts for a portion of the total itinerary fare, the segments booked in V or higher will qualify towards the promo, but not any that are in W or lower.

If I were the MP folks, I would basically be doing a simple pull of all flight segments in V or higher, and pull the segment fares and credit those to each individual traveller registered for the promo.

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