Re: 277V LIGHTING-MOUNTING HEIGHT
210.6(c)
This section does talk about voltage limitations.
I don't know of any other NEC limitation that would keep you from installing 277V lighting anywhere, as long as it adheres to 210.6(c).
I may be missing something myself, though.
I think it may be hard to find 277V fixtures that are listed for some locations. You still have to abide by the UL listing and Manufacture's instructions. If a light is not listed for undercabinet mount, then you can't use it for that.