Ok, VTC-Callback (18.104.22.168) is back up BUT I have a formatting issue on the screen for the logo. I'll fix it later today but for now, it will perform the tests as before. It IS the newer software so you will see a little difference from before (the original Callback) but everything else should be basically the same (and the Return call is MUCH more reliable)..
BTW, this is a free service that I'm funding totally myself. If you would care to donate to the cause, please go to www.vtctest.com
and click on the donate button.