Originally Posted by lowlyblue
Why is the money-only WT fare half the book and upgrade fare? I suspect it's to do with the fare code within WT, but does that mean if I booked the cheaper WT fare I couldn't then upgrade later (even if fare code U seats were available)?
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So in purely financial terms, never mind the leap in comfort, WT+->CW is the best. I suspect that in terms of comfort and service etc. WT+->CW is also a bigger gap than CW->F.
You're exactly right, you can only upgrade certain Y booking classes to W. So if you booked the cheaper ticket at first you couldn't ever MFU to W. However, all public revenue WT+ tickets are upgradeable to J.
And that is why, as you can see, W to J upgrades are regarded as such good value.