Helloooo just your friendly M1 here to talk about the cycle email yall just got. I was complete in July of last year and had radio silence for MONTHS before getting that exact email in early October. Then another late October. Then nothing for a while, and an interview invite in late November. MCW doesn't like doing the radio silence bit that most other schools LOVE, so they try to compensate by sending that email. Its not a hold, just means (from my understanding, not confirmed at all) that they've received your app, looked through it, and it is in consideration. That may sound like a hold, but it's not--your app is in the pile and will be pulled when the stars align. In my mind, what makes up for this long pre-II wait (for most) is that once you get an interview it can be done fairly quickly--I waited maybe a week?--and then you get a decision several weeks after that. Plus, at least for in-state residents, post-II acceptance rates hold steady around 80% from what I've heard.
Also, this will not be the first email like this that you will get, both from MCW or any school. I hope you've got a strong stomach or brought some Dramamine because this emotional rollercoaster is about to get real.