523i in US??

I live in Bishop, CA, which is the perfect place for BMW to do heat testing in Death Valley just East of here, and altitude testing in the mountains just west of here. They're here for their annual testing, and I've been looking around, snooping in their stuff, and sometimes taking pictures. There was only one X3, a Z4, and some Mini Cubmans (Clubmen...?) that were camouflaged, but there were some f10 5-Series, and I found something interesting - one, that was black had black tape over what would be 523i badging, and it was dark, so my picture didn't come out very well, but I did the best I could. I'm not sure if they're going to release it here, but it would be pretty nice!

Cars for other markets get tested in Death Valley.

I would have looked at the speedometer (to confirm MPH vs. KPH). Could be as simple as a Canadian-market (unlikely) or Mexico/South America car.