For 1D04, the lecture consists of a bunch of theory and useless stuff you don't really ever use (but must know the useless stuff for the tests). The tutorials are the T.A.'s sitting and explaining the actual applications of the "theory" stuff you learned, and actually teaching you how to write code in whatever language they're using. For labs, you'll receive a problem on a sheet of paper outlining a task of some sort (i.e. write a program that generates a red circle that grows by 10% if you click outside of it, and shrinks by 25% if you click inside of it), and you have the 3 hours to complete it and submit what you've done before you leave. T.A.'s aren't supposed to help a lot in labs, but they tend to anyway (as long as you aren't explicitly asking for answers).
So, it probably would be more useful to have tutorial before lab, so that you work your way up from the easier/basic stuff to the more complex stuff. With 1D04 though, this is an intro to programming, so if you took programming at all in high school it should relatively be a cakewalk. I had my lab 2 days before my tutorial and it was never a problem, in fact, I probably finished early nearly every lab (I took programming before though, even though I'm not that great at it). The only thing is that it made tutorial painfully boring, since I already knew how to do everything they were teaching, and it's mandatory attendance. Solution: play Pokemon on an emulator. Nothing better to do at 8:30 in the morning...
tl;dr -> If you think you're going to have some difficulty with the material, try putting your tutorial before your lab, otherwise you should be ok. Tutorial for 1D04 is basically "mandatory extra help" sessions.
says thanks to Zimonada for this post.