There seems to be a bit of a problem with upgrades to FreeBSD 10.3-RELEASE. Basically, shutdown -r is hanging, requiring you to manually reset the machine (turn it off and on again). This is annoying unless the machine in question happens to be at a data centre on a different continent, in which “annoying” really doesn’t cut it.
I suggest not using freebsd-update. Basically if you follow the official instructions you may need someone on hand to reboot the old fashioned way.