When Pam is talking with Matt at the football stadium, the image is reversed when the players are on screen.
Matt has been best friends with Bobby since they were kids, yet in the years that Bobby and Pam were married, Pam and Matt had never met.
Cliff sold his shares of Wentworth Tool & Dye to Katherine a long time ago and no longer has a say in their operation. This appears to have been forgotten since now he has a say in what WT&D does when he halts JR's drilling equipment.