I believe it MAY cover living expenses relayed to school (I. E if you have to move, your rent would be covered) but I don't think it would act as a checking account, allowing you to buy food, or just have some spending money.
And I don't think a voc rehab plan could be open ended. I think it has to end with a marketable skill. I don't think VAC would approve a VR plan that DIDNT end up with you getting some sort of certification. Like, I don't think you could say "I'll take two years towards a degree now, and then get out" even if you told them you then planned on finishing the degree after you get out of the VR