Rumor: Sony plans to launch the PS5 and PS5 Pro at the same time.

[Otter]

If there are 2 different models it will be more like what we saw in previous generations like 60GB PS3, or Xbox 360 Elite.

An attempt at a more powerful PS5 at launch will be silly, raw powerwise there will not be much they could do to make major resolution or performance differences unless its compared to an intentionally gimped base system aimed a sub $399 entry point