Just a brief query-
Does anyone know if it is legal to block the track during hybrid mode with your robot to prevent robots on the other alliance from obtaining lines?
The bump-to-pass rule is not in effect in hybrid mode. As such, I don’t believe you can be flagged for impeding traffic. However, you won’t be able to block the lane all that much, since you can only extend to 80".
Yes, you are correct about the fact that we couldn’t take up too much space. I was just curious. Thanks so much for your help!
Who says a blocker needs to be everywhere at once? As long as you can see 'em coming you can get in their way. 
Of course, you’ll want to think this through strategically. Is it likely that the other alliance will cross both of their lines and get to where you’re blocking? Is it likely that YOUR alliance will get to that point, at which point you’ll be in the way? Are you confident enough in your robot (both mechanically and in programming) that you won’t go over the line and get a penalty for going against traffic? Is it more worthwhile to go after the 4 easy, and 8 doable points? Or is it a good thing to have a defensive autonomous to pull out of your bag 'o tricks, should it become necessary in the final rounds? All things to think about…