*Saul faces the camera*
"I bet you're wondering how I ended up like this."
I think it would be pretty neat to see BCS fill in some of the gaps on BB. And it would be very uncharacteristic of the show not to show something that both would be interesting to see and that the fans would really want to see. Look at how they're clearly enjoying bringing back past BB characters. If you can't tell that Walt and Jesse will be the main event of the cameos...
"My name is Saul Goodman, and I'm the fastest con-man alive..."
If they eventually do a full post-BB season I could see the cold opens being flashbacks to the people he knew as Jimmy McGill reacting to events throughout Breaking Bad.
Assuming these people haven't met gruesome fates by that point.