That depends on your openelec settings. There is an openelec settings addon that allows you to auto download updates, or if that isn't activated you can "check now".
If you check now it will download the new version, reboot (twice) and you then have the new version.
I just checked in the openelec settings and I am still on openelec 4.0.0. I have enabled automatic updates under "system", but it stays at openelec 4.0.o (Gotham 13). Any idea how to update to 4.0.7 without doing it manually.
Try clicking "Check for updates now". If that doesn't work, then an earlier update may have failed or been cancelled (which can stop subsequent updates from succeeding - see issue #
3301) or your internet connection isn't working.
Manual updates are not difficult, just drop the new 4.0.7 tar file in the Update folder and reboot.