Isn't the processor board in the gimbal?
The sensor of the P3A and P3P is the same. It seems that inside the camera there is not much more than electronics to drive and read out the sensor. Look at this picture from a video where the replaced the lens.
View attachment 44883
Maybe the camera (including board) is also the same, except for the marking 4K.
Could the only difference be the gimbal board and the ventilator on the gimbal?
That is what I am thinking. From a cost perspective it makes sense to just mass order one camera and gimbal unit. I still think that the 4K camera has the extra 4K processor chip as I read somewhere, that makes sense. So essentially in production they use the same parts but for the top section of the camera/gimbal unit they supply it with the 4K motherboard, and a nice 4K stamp on the front. I would do the same if it kept production costs low. They can also use universal parts in the repair center. I could even see a possibility where if the 4K capable boards were cheap enough they would simply lock down some as 2.7K with chip firmware. Didn't they already do that with Naza and Naza 2 or something like that? I was an electronic field repair tech for many years. The boards or even whole modules are so cheap these days the company I worked for would throw complex boards away rather than ship back for even simple repairs.
P.S. Look at what they already did. 1080p became 2.7k with some firmware magic.