The last table read happened to be on Rico Rodriguez's 21at birthday which was July 31, 2019. They also had to a tradition of including the kids in the table read at a certain age, but because Jeremy Maguire who plays Joe was not even 9 they made an exception for the last one.
The last episode of the series to be directed by Steven Levitan, who is one of the creators of the series.
Luke is going to the university of Oregon. Ty Burrell is a university of Oregon alum.
Arvin mentions Hugh Grant when talking to Alex. In This is Us which Chris Geere was in his characters eventual wife Kate says at one point that when she was little she imagined herself with a Hugh Grant type.