A fix to the bug is in development, but we don't know when it will be released yet. Hopefully soon.
It is possible however to opt out of the preview in the app and then restore Windows Phone 8.0 using the Nokia software recovery tool. I wouldn't recommend doing that unless you're sure that Cyan is ready for your country/region/carrier - the downgrade is a bit of a pain and if the update isn't available, you're stuck with 8.0.