Dear openSUSE Tumbleweed users,
It has been a long road, but we have reached the destination: Python 3.8 has been checked in to Factory after the Staging was finally passed. We spent two more days working out a bunch of non-ring failures as well, trying to make the switch as smooth as possible - and openQA agrees with us: openSUSE Tumbleweed - Snapshot 20200309 will contain python 3.8 and is currently in progress of being synced out to the mirrors.
As this is a major jump, I'm (unfortunately) almost sure the update won't reach you without you noticing it. There is potential for many packages not being rebuilt (or rather, having failed to rebuild) - and, depending on what you have installed, zypper dup might ask you to eliminate some packages that are no longer compatible (could be also coming from 3rd party repos, that did not yet rebuild against python 3.8)
So, please be careful with your next zypper dup and if there are breakages happening, feel free to file bugs.