Definitely seems slower to me too. 
And on top of everything being slowed down, it appears I’m randomly unable to make any calls. It shows good reception - just won’t dial out (and presumably doesn’t allow incoming). It requires I restart (which also takes forever).
Hi @Dake - does your calling start working after restart? If yes, does it stay like that or does it break after some time? If you don’t mind, could you share your carrier as well.
Regarding performance, we can track it here.
It does start working after restart. Failure seems to be somewhat random, though may be tied to when the phone loses its signal (due to flying) and then reacquires it.
I’ve also turned Wi-Fi calling off and it hasn’t done it since.
Carrier is T-mobile.