I also had a problem with the update to 1.2.5. Versions 1.2.4 (somehow on an iPad) and 1.1.1 worked fine. It would connect successfully but not pass traffic. This is a split-tunnel situation where not all traffic is destined for the tunnel.
I did a packet capture on the openvpn-2.4.4 server and noticed that no traffic, besides the periodic pings, was being sent between the client and server. I then did a ping from the server to the client and received responses. The tunnel was working, but I suspected that the routing table on the client was not correct.
I had to add:
push "route 192.168.20.0 255.255.255.0"
to my server config. It appears as if the network as defined by the "server" directive is not being added to the routing table of the iOS device. Adding the manual route push fixed my problem.
Hopefully this is helpful to others.