Seems we might need a thread on PY quirks, advantages, and disadvantages. I wasn't aware that PY Flex wouldn't eupgrade same way as a Latitude (and maybe that wasn't the problem here-just AC IT?). Of course I have only bought PY Flex once and either go for paid Business, Latitude, or when I was feeling really lucky, PY low, for international flights.

A question:
Why does PY low beat out Latitude for eupgrades? (all other things equal or very unequal at times)

Then my questions (for another thread)
Why isn't PY available for a flight pass (maybe it is now?).
Why isn't PY available for a World Companion Pass?
etc etc.