Ranked Decay - Immediately?

Not at my usual set-up so I'm only playing when I have to, I am very close to not getting the rewards I want. The other day I hadn't played a ranked game for 10 days, and that's when I'm supposed to decay, right? (I'm master) I didn't decay. I'm in a situation where having one extra day could mean a lot, so does anyone know when you start to lose LP after you hit the required amount of inactive days? Thanks a lot, and of course if it gets the point where I can't get the master border, oh well. I'm just a little anxious at this moment.