Sorry if I missed this and it's already been posted, but I did not see it.
I wanted to share that, as of 7/17, you can now use SM to upgrade VS flights.
(
https://www.delta.com/content/www/en...d-updates.html)
I called to try to upgrade my r/t booked in premium economy this fall. The first agent was not aware of the new rule, and insisted that it was not permitted.
HUCA. Good agent, she knew exactly what I was talking about but there was no space available.
However, learned that it would only be
20K miles each way from prem. economy, plus the UK luxury tax (agent said around $100). And, there are often GREAT PE fares available for advanced purchase. I purchased these VS A PE tickets for aprox. $900 a few months ago. This means that, if you found the right tickets and available space, you can fly VS UC for aprox. $1k and 40K miles r/t. That's a fantastic deal.
You can also upgrade from Y to PE, and Y to UC, but I did not get the numbers.
There is no waitlisting available. Fingers crossed that I will find open seats before the flight. I'd gladly spend 40K miles and $100 to upgrade SFO-LHR.