We have an iPad that is running iOS 8 and can't see that iOS 8.0.2 is available. This id true from both the settings app and through iTunes. Other iOS 7 and 8 devices on the same network can see the update and have been able to update. We've done a complete "Settings -> General -> Reset -> Erase All Content and Settings" but the reset OS also can't see the update. A restore from iTunes didn't seem to fix the issue either.
We also tried to update the OS from iTunes and are being told that the iPad is up to date.
This device at one point was managed by MobileIron, in case that makes any difference (we suspect it might). From our MobileIron interface, the device is no longer managed and the MobileIron app has been removed from the device.