Here's hoping all goes well, and that, once they tell you they're going to spring you, they do it right away.
When I was in for a surgery some years back, the doctor said, about 9:00 a.m., "We're releasing you today." Fine with me. But there was paperwork, and this, and that, and I finally got wheeled out to the car at 4:30 p.m., right in San Francisco rush hour traffic. Even with the sneaky roundabout that we took to avoid the freeway traffic north, it took three hours to get home (a distance that is theoretically about an hour and a half's drive), and the bag from my post-op catheter was just about to burst when we pulled into our driveway.
Edit: hadn't seen the message that you're home when I did this reply earlier. Good to know you got home before you got too frustrated.