Just had my first Lab of this year's WWDC, and as always, it was incredibly helpful.

I will say though, that the cheat code for super constructive Lab sessions is to have prepared an example project which narrowly focuses on your problem area. Share your screen (with the Presentation theme selected) and then walking through your code with the engineers who worked on your framework is incredibly powerful. Also, have an open Notes document with your question list to make full use of your time.