Isn't it strange how sometimes you suddenly start spotting a lot of examples of a new(ish) usage?
Is it proper grammar? That depends on whether you accept "below" as an adjective. Some dictionaries don't, a few do.
It just sounds awkward to me and it's not like there was anything wrong with writing "the (whatever) below".
Another one I've noticed is that "So" seems to have replaced "Well" at the start of answers to questions (e.g., at the TED talks). For example, asked how the person got into writing, he or she might say, "So...I was really into reading when I was a youngster..."
Neither "Well" nor "So" is necessary but I'm mystified how these things spread.