submitting your app
I would also SUBMIT EARLY. I learned this the very hard way when I was applying for my MPH through the SOPHAS system. I remember thinking that I was in great shape submitting two days before the deadline, but SOPHAS kicked my entire application back to me and refused to verify and send my application to my schools because I had an error on my transcript. So I spent the next 48 hours almost in tears calling various administration offices to get this fixed to still meet the application deadline. My point here is that just because a school has a certain date/deadline, just keep in mind SOPHAS is on their own system and schedule and if they take too long to process your materials or kick them back, then that's on you. So just to avoid any last minute panic, I would try to plan ahead so that your application makes it in a few days earlier and nothing weird happens.
Then take a break!!! Enjoy the winter holiday break. Be proud of this HUGE accomplishment you just completed in just submitting and taking that bold step to apply to Phd programs.
Oh and another rule of mine...STAY OFF GRAD CAFE. Block the website if you have to. Please please please listen to this, as it really will have benefits to your mental health as you are waiting to hear back from places.