Starting 15 day challenge

Hi, so I'm starting a 15 day challenge. I have never gone more than 4 days without an MO or 10 days without a PMO for the past few years. To me, this goal will be a challenge. My ultimate goal, of course, is 90 days, but I don't think I am ready to reach it quite yet. I have my PMO counter set up for it. Currently, it is inaccurate because there were other resets and relapses before the one indicated (however none came after). I will consider M or MO a reset, and anything with a P a relapse. The goal is to go 15 days on hard mode. I'm going to be keeping a log of it in the 20-24 journal, and when I (hopefully) complete it, I'll be able to give myself a new challenge in this forum.