My enthusiasm for CentOS8 is limited.
My enthusiasm for a hard migration even more so.
So how much time do I have before 4.3 becomes inoperable?
oVirt 4.3.10 is approaching GA and we expect 4.3.11 to be released too before declaring 4.3 at the end of life.
After that, 4.3 should keep working till CentOS 7 or any other repo on the system will break it with some incompatible change.
I totally understand system administrators' point of view and how difficult it is to find a good maintenance window for a busy production environment, ensuring backups are recent enough, check new requirements matching, give it a try on a test environment if it's available and so on.
That said, I would really encourage starting to plan a maintenance window for upgrading to 4.4 as soon as practical.
It will be easier to help with upgrade from 4.3 at this time than 2 years from now when 4.3 can be broken (or new hardware replacement will be missing drivers on CentOS 7) and there won't be any additional release for fixing upgrade incompatibilities.
