There might be a place for 800, but a very limited one. If the orange peel is fine, tight, or even dry, there's no point. In fact it's probably way too much because the mils probably aren't there. But if there is an area where the finish went on wet, almost too wet, you might see a zone where the peel gets into a kind of rolling look, the stage just before a sag will form. These are the kind of areas that can be rescued and flattened with a hard block and some 800. But all that said, everything in this thread about 800 scratches applies. Just a rule of thumb, I'd probably count on sanding twice as long with 1200 as I went with 800.
I tend to get that rolling look sometimes on white truck bed sides. Also because like Hub used to say, I paint in 3D. Dark, damp, and dirty.