I'm here with an update that the blog is coming on the 20th. As we said in Rubi's original post, it takes us time to lock text down and get it through our publishing pipeline. Please accept my apologies for the delay from our communicated schedule.
I really hope it's not "Were making it up as we go and we don't want to admit we forgot about legendary runes so we need more time before we disappoint you."
I honestly find it hard to believe they just forgot about legendary runes, in my opinion it's more likely they didn't properly assessed the consequences of their changes, it doesn't look good either way unfortunately.