We have this same issue at our school. It shows success in the logs, but most of the time doesn't update the iPad.   What I don't understand, is that when it does work, it starts automatically. I don't have to manually start the install. In all cases, no account is logged in. If I do accidentally leave an iPad logged in, the logs will tell me.   A classic scenario for updating the iPads, would be setting up about 4 to 5 iPads up on a bench, all logged out. I would then manually send the update to those devices one at a time. All would eventually show success in logs, but only about 1 on average would start to update. ... View more