I discovered that there are only certain forms that are locked, in my case it's the one to do with accumulated capital gains/losses. It said it would be updated on March 2nd. (Don't ask exactly where I found the info, I probably couldn't find it again!) So I'll check for an update on the 2nd and hopefully be able to print and file then. At least that explained to me why I was able to print and netfile my kids returns that didn't use that particular form.
