I think the biking strategy is brilliant. You have removed all external delays (late cab, traffic, car trouble) and you also will get your body and mind reved up on the way to the test center. Just one water bottle for the AM ride and one water bottle filled with your favorite libation for the PM drive! Just watch out for cars and pedestrians! Good luck.
I actually don’t mind. The route is pretty straightforward and in the morning around 6 15 am when I leave, it’ll take me max 45 mins to reach. But yes, the ride back home will be crazy but eh, i’d be a happy man having finished the exam and all 😀