Hi,
We are planning to release the first candidate of 4.3.1 on February 20th[1] and the final release on February 26th.
Please join us testing this release candidate right after it will be announced!
We are going to coordinate the testing effort with a public Trello board at https://trello.com/b/5ZNJgPC3
You'll find instructions on how to use the board there.

If you have an environment dedicated to testing, remember you can setup a few VMs and test the deployment with nested virtualization.
To ease the setup of such environment you can use Lago (https://github.com/lago-project)

The oVirt team will monitor the Trello board, the #ovirt IRC channel on irc.oftc.net server and the users@ovirt.org mailing list to assist with the testing.