I don't know if this had been discussed somewhere previous to the release of Generations Thunderwing, but I just saw when unpacking the figure that there's a different head on the instructions.
If you check the instructions that are available for download via Hasbro; Thunderwing, the right head is depicted, but not on the instructions that came with Thunderwing.
It is probably a upcoming figure as we seen before on other instructions for other figures.
So people, speculations. Any idea what figure this might be?
Here's a picture that i took from my instructions;