Howdy Tube Jockeys,

A quick bit about me... 1,700,000 lifetime on United. Made Global Services on my own about six years ago, held it for three years... then business traveled tailed off for a couple of years and I was gold for the last few years. Flew a lot in 2017 and am back at 1K for 2018. Most all of my travel is business related and paid by my client (I bill them). I confess I am pretty ignorant about fare classes and how they impact the chance for upgrades, be they CPU, RPU or GPU. This year looks like another heavy travel year. So why wouldn't I specify certain fare classes when searching or and booking flights to increase my upgrade chances? Sure, they ticket might cost a bit more, but I don't have any "lowest possible price" agreements with clients. Just "coach" for domestic. On international, most clients pay for business class but I have one that will not and I need to get smart about booking international coach in a way that increases my upgrade possibilities? Thanks for any advice.