What time does Warped tour end?(+advice?)?

I'm being dropped off and picked up by my mom, who has no cell phone... so we need to have a time to tell her to pick us up beforehand. I don't want to have to wait for her when it's over, and I don't want to leave early. I've been hearing "8 to 9" or so... does anyone have anything more definite than that? I mean, I could let her borrow my phone, but if I decide to split up with my friends inside to see different bands that would make things more difficult for me. I'm going in Mountain View, and I thought of getting a close hotel (there's some like 2 miles away) and just walking back when it's over.. but there's the problem that a highway separates the venue from all the hotels and everything. And I'm not walking across a highway. So...any ideas on what I should do?