So I filled it up again and same deal. Made an appointment at the dealer which happened last Monday and took it in. I was willing to bet they'd say it was a sending unit or level sensor problem. I figured that since the 350 had that issue and it seems unlikely a long lasting LED would go out.
They called me to tell me to come get the car a few hours later and they'd call me for a follow up appointment when the parts came. They ordered a whole new cluster under warranty...
I guess it's the LED according to them, we shall see probably next week.