It looks like we have the first pictures of an i3 with the REx option. According to Drive Arabia, this photo was taken in Dubai recently. Speculation is the i3 is there to conduct hot weather testing.
In the photo you can see the open port above the front wheel. I've never seen any i3 photo with a fuel door there. Every picture and video I've seen to date shows only one door and it's about six inches above the rear passenger side wheel. If you look closely at this picture you can see the outline of the small door there. I believe this is the door to the charge port and the opening you see above the front wheel is where gas will go for the optional gas range extender (REx).
This i3 looks like it's pretty close to production beneath the swirly camouflage. Hopefully we'll get a peek at what's under there sometime soon!