The Championship games are always 3 and 630. At least for as long as I can remember. They do move the AFC and NFC around. Last year the Chiefs/Bills were 630 and the Eagles/Commanders were 3. Some of it depends on who the host team is, but this year they are both western teams so the premier game is the Seahaws/Rams. If the Bills had beaten the Broncos I don't think it would have changed the time because you'd have an Eastern team and a Western team hosting so it makes way more sense for the Eastern team to play at 3 (local time) and the Western team to play at 330 (local time)
Start times used to be 12:30pm and 4pm until the early 2000s. Think the first Pats-Steelers was the last 12:30pm start.
Championship games are on a rotation. In years where the AFC team will be the Super Bowl ?home? team, the AFC title game gets the 3pm start and the NFC game gets the 6:30pm start then vice versa the years the NFC team will be the Super Bowl ?home? team. The geography doesn?t matter.
