After eating some cookies I felt lucky and flashed RTSP firmware .
So when v3 is on lan1 192.168.1.x in one building RTSP works great over UDP.
Wyze app and Tinycam app are on lan1.
When I move camera to other building on lan2 192.168.2.x, RTSP works only over TCP.
Both lans interconnect over wifi bridge.
In wifi bridge setup there is no way to block UDP
Wyze app displays live stream in both scenarios but it uses http.