With upgrades becoming few and far between and F fares skyrocketing, I am thinking about booking an extra seat in Y for some travel next year for extra space. Never thought about doing that before, but being stuck in the back like I was for the first time in years this weekend to EWR and back, I was thinking it would be a good strategy.

First, I assume this is allowed? Second, how can it be done? Online or do I have to call a GS agent? I'd only consider doing this on MP heavy routes, like IAH-EWR-IAH, which is what I was on the this weekend. Even when booked 3 months out and PP put on the ticket, no upgrade.

thanks!