From the release notes:
This is not just applying to new installations. I upgraded my secondary server and my docker custom network type was changed from macvlan to ipvlan.
Solved
Minor
I've issued a fix for this, but in the meantime when you make a selection - either 'ipvlan' or 'macvlan' it is applied correctly when you click 'Apply'. The issue is the Gui is not displaying the current setting correctly.