Early rather than late for me, but 90 minutes is too early. I've spent my whole life in a pattern of 15-20 minutes early.
On a related topic, I live about 40 miles from the nearest VA facility. The VA runs a network of vans in conjuction with the DAV (Disabled American Vets) to pick guys up all over the countryside for their appointments. Most times, the van will be out like at 6-7am picking a half dozen guys up, and get us all to the hospital at 9am. We all do our various appointments, but have to sit around until maybe 3-4pm until all the appointments are done, and then the trip home. I've shown up in the various clinics maybe 2-3 hours early for my appointment, and a lot of times I'll get in way early, and be done, only to have to wait another 4 hours for everyone else to get done. I hate waiting, but an MP3 player and a pocket-full of brownies helps to pass the time. The Green Team waiting room is my favorite place to hang out. For the non-vets, that's the looney bin, and I've met some really interesting guys there, and had some great conversations. One time a guy came in with real long hair and beard, and looked like he hadn't bathed or combed his hair in months. He sat down with a wild-eyed look and asked me if I thought he'd have to wait very long for his methadone treatment. It was kinda difficult to get a conversation going with him, but I enjoyed trying. Passed the time, and the brownies really helped.