This never happened before Catalina: occasionally, when I restart my MBP, rather than going black, my screen changes to the Catalina screen. It may also happen when I shut down, but I"m not sure.

Anybody else seeing this?

More: I should have mentioned that the Catalina screen is not my desktop screen; it appears from out of the blue.

I see that when shutting down but not when starting up.

I don't see it when starting up either, only when I restart or, possibly, shut down, and only very occasionally under those circumstances.

I have seen that behavior since the first Catalina beta both staring up and shutting down. The only way I found to stop is was to change my desktops to Catalina. 🤷‍♂️

I have also encountered an annoyance where the system seems to lose track of the exact position of the edge of the primary display and the desktop will track the cursor ¼" or so left or right between the two monitors. So far, this has not occurred in 10.15.4 beta 4 🤞

I'll "suffer;" my chosen desktop is more important than squashing a momentary annoyance.