On Thu, 14 Jul 2016 15:42:48 -0700, John Robertson wrote:

Jeff's point is you are at the maximum recommended input voltage,
anything changing there and the device will go south,( east, west, or
north - ) which may prove catastrophic.

Yeah, there's not much headroom for sure. I'd sooner have used a LM317AHVT
but I don't have any 'in stock' here - but that's what I'd have used if
I'd had one.