I would say the opposite: land this today so that it can get in F28 Beta
(tomorrow starts package freeze for the beta release), and don't do a
post release update that changes the drivers ABI.

This should have happened via the System Wide Changes proces, isn´t? At less a Freeze exception should be requested, even with WorkStation using wayland by default the Xserver is critical for the others spins, in the works case can land in F29.