I think you can push ios updates from console to device, BUT your users must to confirm that he like to update his device. Without this you can not update this device.
I assign ios update to user group and choose "download and install" so I see in console that update is already download on device but user not accept this. After that I created compliance policy and email notification for every day to users which are not update devices.
May be you can post screenshot with error message.
Sorry for my english.
Regards,
Dimitri
