Apple might have realized there was an issue and pulled the update. It was in the home app for me but never got past update requested step. I rebooted my iPhone XS Max and the HomePod. Now it is telling me that it is up to date on ios12.4 again.
Why would they not incorporate wireless CarPlay into this? Wasn't alpine the first company to release wireless carplay aftermarket head units? I was really hoping to see more than a couple of new wireless carplay stereos released at CES. Looks like I still only have about 2 options to choose from.