Originally Posted by GagaPilot

I would be cautious about booking C+ on a flight with seats available on the 2 side only, and nothing available on the 3 or 4 section if having no one next to you is a concern.

As an observation I have an upcoming (domestic) flight on an A330-300. I received an UG to C+ at booking as a PM. The seating configuration is 2x4x2. The middle two seats in the "4" section are blocked. The seats on the "2" sections are not. I chose 12A, and a few days later I noticed someone was next to me in 12B. It specifically showed as occupied, and not blocked. I moved to 12G in the middle section so the middle two seats of that section are blocked. Note: I am not concerned with having someone next to me, I simply just chose 12G to have more space.

I am also on a domestic flight on a 767-400 as well. Configuration 2x2x2. In the middle section I noticed a blocked seat will appear after you select a seat, but on the right "2" section, the aisle seats are blocked to begin with. I chose a window on the right. But, on the left "2" side, both seats are available and none are blocked, even after selection.

So, choose carefully.