Thanks!
It's okay, I kind of figured it out after reading the first few responses in this thread. I'm still interested in some sort of value calculation in terms of what I lost in MQM's (FF points? I'll use the glossary to find out!), and a comparison of the extra fare I would have paid. I'll ask my TA about it.

In the end, it's all a lesson learned. I think that for where I'm at right now (somewhere between needing to fly economy all the time and being able to fly Business/First all the time) I want to have access to those Premium economy seats wherever possible.