You should sync your iPad often. Remember there is no backup of your iPad.  Once you sync it to the cloud it will be backed up.   Occaisionally after syncing you will be notified that there is an update available and give you the option to proceed or decline.  If your iPad is not up to date it will continue to notify you after each sync. It is best practice to accept the update as soon as possible but please be sure you have reliable Wifi and time to let the iPad update.