The 4.20 kernel was released just before the end of the year, but the
first stable update should be dropping in the next day or two. We
have a 4.20 test day scheduled for Tuesday, January 15th. Depending
on the results of that test day, Fedora 29 will be rebased very
shortly afterwards, followed by F28 approximately a week later. Of
course the results of the test day could end up changing this, but it
is the current plan.
Thanks,
Justin