Best time to get a new TV is the week after the super bowl, get the tvs that were returned. I imagine the same applies to world cup and other sporting events that prompt people to buy a massive TV just to return it a few days later, after they show it off at the party.
IIRC, new TV models usually come out in late spring / early summer. So best time to buy should be around then.
Post CES?
Yes. New products get announced at CES and start being available in a couple months. Retailers need to make room for inventory and sell off last years models.
I haven’t looked for a TV in a long time. However Amazon frequently is not the cheapest place vs how things were a decade ago.