Originally Posted by
Rousseau
And on long haul, presumably the best bet is a WT+ before UuA? Is there any distinction between UuA at point of booking, and retrospectively. In terms of Avios/monetary cost?
Yes, on long-haul, buying WT+ and then doing a UuA to CW is a very good value use of Avios.
This is particularly so if you earn extra Avios from status. On one or two routes, a Gold or Silver can earn more Avios from the underlying WT+ ticket than the Avios cost of the UuA into CW.
There's no substantive difference in cost whether you do a UuA at the time of booking or subsequently. The only thing that might vary a bit is if there's been some change in the taxes, fees and charges on the route, but these are usually small.