The fog is clearing on booking and upgrading

Thanks to all the really helpful posts on here, I'm starting to find my way through the misty maze of booking and upgrading but I'm still a bit lost on booking a low code and then paying to move it up for a miles upgrade.

Am I paying for K and then only paying to upgrade it to W or S for a G on the basis that a G might not appear? Or am I doing it that way because you all know that it works out cheaper than buying W/S to start with? Do you sometimes find that it would have been cheaper to buy Z to start with?

I'm sure you'll all sigh at this but it is so useful for a newbie like me to get information from you frequent flyers who seem to know every aspect of such a foggy maze.

Thanks.
Whiterose

There's a few different factors to take into account when booking any fare ,
To give you some examples of my own bookings , I've booked Z fares because I've been happy to pay the price and wanted the Tier points and miles , also booked M fares and upgraded to G's because I didn't want to spend too much and wanted to use some miles up , I've booked k's and stayed there because I was happy with that .
There really is no right or wrong in my opinion and it all depends on what you want and what you are prepared to pay for it ,
A belated welcome to vflyer by the way

Am I paying for K and then only paying to upgrade it to W or S for a G on the basis that a G might not appear?

Yes, that's right.

Or am I doing it that way because you all know that it works out cheaper than buying W/S to start with?

No -- it probably won't make any difference. The only situation in which it will really matter is if you could have bought an S to start with, but instead bought a K and subsequently want to change to an S, only to find that there are no more Ss left to buy. I hope (but don't think) I have expressed that clearly!

Do you sometimes find that it would have been cheaper to buy Z to start with?

Yes, it is possible that a Z might be cheaper and this is something worth checking, particularly if there is an UC sale or if you are finding you need to buy a full W fare at the outset in order to upgrade with miles. Best to call the UC line to book as they will be familiar with these things.

Good luck!

Thanks so much to both of you. It's not all to do with phases of the moon and Richard Branson's date of birth after all. I'm about to book flights in Sept/Oct LHR/EWR for a family celebration so having some idea of what I'm doing is a real help.
PE isn't too bad unless the person in front fully reclines their seat for the whole journey which is enough to make me feel I want UC every time.