ooh I see, in Pyramids of Mars pt2 the Doctor takes Sarah Jane to look at 1980 if they don't stop what happens in 1911, and it's an apocalyptic wasteland, so when you're watching the Beatles episode in 2024 you're supposed to go like "hey just like in Pyramids of Mars!" and then you're thinking about the exact right episode.
You know, if you already had watched all of Doctor Who before this year instead of say, hitting the current plot twist related episode today. :P