I think there are tons of rumors about the reveal being in Feb, because the PS4 was revealed in Feb 2013. While I agree that Sony is highly likely to use the same timeline for the PS5, I don't think there is much more substance than that to the large majority of rumors.
Well this is Sony's fifth consoles launch so we can look at there history. Also, We are less then 10 months away from the launch window.
I really don't know what Sony will do this time around, I expected they were going to announce their new controller at CES 2020 to start the hype.
I think Microsoft and Sony may play a game of chicken, so they can make last minutes update to improve performance base on the competition console specs.
2020 is going to be an exciting year for gamer regardless which console you support.
Any last minute updates are impossible after chip is finalized. The only thing they can do at this point is bump the clock speed. We already know that MS has finalized their chip. For Sony, we don’t know yet but I doubt they haven’t finalized their yet.