I’ve heard people say you should start a new game. Which I did. But I think you’d be ok to jump in if you wanted. There’s a new neighborhood that it mostly takes place in. To start it, you have to complete some main game story mission about 3/4 of the way in, if I remember correctly.
This was a fun one. Glad to see he’s finally getting some paper form Woodland Scenics (or at least free stuff) considering how much free advertising he’s given them over the years.