https://crankyflier.com/2018/11/15/a...three-markets/
The buy ups are currently $15/$25/$30 each way on short/medium/long haul.
Of course there's lots of weirdness on the website when you try to go book it, including misaligned and poorly formatted pop-ups. On the initial seat map it's not clear what seats are and aren't available for Saver. Then, when you can select seats, they are more clearly indicated but it won't let you buy up out of Saver to a regular coach seat. However it will sell you a Premium Class seat -- for $6 more than if you bought out of Saver and selected Premium -- AND you're still stuck un-changeable and un-upgradeable to F.
