The "winehq" package is not part of Fedora. That is provided by the winehq.org website. The Fedora package is called "wine" and has not changed its name. 'sudo dnf update wine* --enablerepo=updates-testing' to update your existing Fedora package.
There is no upgrade process because there is nothing to upgrade from or to. Wine-staging was just a series of patches applied on top of a release of Wine. It was not a fork or separate set of tools. You will not lose any installed software.
Intel has now announced that Broadwell and Haswell CPUs may experience rebooting with these microcode updates. I have not been using the update for long enough to confirm if this is the case, but people should be aware of this new issue.