It's not odd to get updates so close together- they're different builds (bug fixes) rather than version updates. When a new version comes out you can expect to get a few updates over the following week or two, then they slow down.
Sometimes an update fails to install for no obvious reason, but usually it's because the owner is doing something with the car when it's installing. Leave it alone. Go far away from it. Best to let it install overnight (that's the default setting) so you're not tempted to "check on it".