Some people claim that you can perform updates over the air if you've rooted the ROM that came with the device (4.1.2) and all it will do is remove the root, however others (the majority) claim that you would have to go back fully stock (unrooted) in order to be able to perform updates over the air. From my experience, I wasn't able to do it while rooted and I got an error message after downloading the OTA update saying (Your software has been modified).