CEH V11 vs V12
If you're only 4 hrs away from completing v11. I would say complete it. The certification is still valid. for at least a year of not longer.
If your employer has mandated you complete v.12. Then I would worry about switching.
Do not ever switch your progress on the track that you've started unless you have a good reason for the switch (e.g., employer policy, employer is willing to pay for a new exam and study materials for you.).
As of right now, we've not completed the production of v12. We're still in the middle of recording this show. I am expecting it to be complete this Q1 but that doesn't matter to your point.
But a blog post helps you to know the difference here: https://www.vinsys.com/blog/difference-between-ceh-v11-and-v12/
"...There is an add-on in the attack techniques, too, in the newer version of the Certified Ethical Hacker Credential. Earlier, 420 techniques were a part of learning in course training, but this new version consists of 519 attack techniques...The operating system used for labs will be the same in both versions, i.e., Windows 10, Windows Server 2019, Parrot Security, Android, and Ubuntu Linux. Windows Server 2022 is now part of v12. "