I don't work for Apple. I am not affiliated with Apple in any way. I answer questions in ASC, apparently quite successfully, as somewhere between 4,000 and 8,000 people have said I helped or solved their problem.
In the thread I found several posts from people who opened their phones and found a connector had come undone. While I don't recommend this approach, how could a software update cause a cable to become unplugged? I also saw several from people who fixed the problem by doing a DFU restore, which would indicate a software problem, most likely memory corruption. And some who also reported WiFi issues. As WiFi is critical to GPS accuracy they are related, and the radio chip that handles WiFi, Bluetooth and GPS is fairly delicate. So that's at least 3 different causes for the same symptom.
To refine my WAG, there are over 1 billion iPhones. There are 278 posts in this thread, but most participants have made more than one post, so I'll assume 3 per user, which means the number of different people reporting the problem (even throwing in the people without a problem who just respond and try to help) is under 100. 100 / 10^9 is .00000001, or 0.000001%; my initial guess was pretty close. Even granting that only 1% of the people who have this problem are represented, that's 10,000, or .0001%. As reported problems go, that's a very small number; small enough to be random chance.