I have been try to updated my blackberry z10 since i got it. It can notify my over updated but when it started an reaches 10% it give an error of the wifi.
The updated will come like 10.2.1.2102 when try to update it jst continue updated the whole day
Go to Settings > Software Updates and check for updates. You can also use BlackBerry Link to update your OS. If the OS you wanted is not yet available in your carrier, you can opt to use third-party applications like Sachesi or you can also download the appropriate autoloader for your device. Be warned that loading an OS via autoloader will wipe your device, so backup everything first.