User blog comment:Bobbricks123/New Glow System?/@comment-24911451-20150123200017/@comment-25257441-20150123202836

Actually, something similar happened previously, when you needed 11 Achievements for the Green Glow, although the Achievement said that they were just 10... After some time, they made the Achievement to say that you needed 11, not 10.

So, I think we should wait and see...