Ford (F) and Rivian hosted a joint conference call Wednesday morning announcing Ford's $500 million investment in the privately held automaker. They also said that they would be developing a joint vehicle together, to be branded as a Ford automobile.

The two companies didn't specify what kind of vehicle they would make, but they all but admitted it would be some sort of pickup truck or utility. Of course, that is pretty much what Ford has said about its entire portfolio, so we would be shocked if it were otherwise.

On the conference call, however, the most important question came from an analyst who was asking what the joint announcement means for the prospects of the Ford-only, all-electric F-150 pick-up truck. Why not incorporate Rivian's technology into that vehicle?

This was an interesting question because it had been widely believed that the all-electric Ford F-150 is very early in its development. Therefore, it would make perfect sense to put Rivian's technology into this pickup truck.

But the answer from Ford was no. Why? Because the all-electric F-150 is already mid-way through its development cycle.

Whoa! What does that mean?

Normally it takes approximately 4.5 years "from sketch to showroom." If the all-electric F-150 is mid-way through that development now, that would imply it will be in the showroom in 2 to 2.5 years from now. That means it will be at your friendly Ford dealer by the second half of 2021 at the latest.

That is an important confirmation. Tesla (TSLA) has said it will unveil its all-electric pickup truck some time later this 2019. There is almost no scenario under which it will be in volume production by mid-late 2021. Tesla needs to raise money, then order and plan for factory capacity somewhere. During that time, Tesla would also have to undergo a torture-test program, so that the truck can tow and not be sensitive to rain, snow, ice or cold weather. The second half of 2021 would be a best-case scenario, to put it mildly.

I have no doubt that Tesla's pickup truck will look beautiful, and that Tesla will promise that it will have all sorts of amazing specs, such as a long range. However, when it comes to a pickup truck, who are you going to trust to have done their homework to make a reliable and rugged truck that has been properly tested? That would be the incumbent truck makers, such as Ford, General Motors (GM) , FCA (which owns RAM), Toyota and Nissan.

We have a sense that General Motors is working on an all-electric pickup truck as well, but it has not yet given a date for its availability. Based on what Ford just told us, it would appear that an all-electric F-150 by the second half of 2021 would be the first to market.

And that's pretty big news.

At the time of submitting this article for publication, the author was short TSLA and long GOOG and GOOGL, AMZN, FCAU and GM. However, positions can change at any time.