I just upgraded from core update 148 to 149.
When I tested this in my virtual test bed setup there was no problem.
In my production system, after reboot all network communications ceased to exist.
I connected to IPFire with a serial connection and found that the green, blue and orange network interfaces had been unset. Reconnecting them to the correct network mac addresses via setup and rebooting brought the network back to life.
Not sure what caused the problem but everything seems to be working ok now.