Update: Mercersburg Academy
Decisions will be mailed on M9 and emailed on M10 after 3 p.m. EST
Not sure than any statement made will be correct for ALL schools. MOST schools that I know of will either email the decision or post it on a portal on M10, as early as 12:01 am and as late as 5-6 pm in their local time. MOST schools will also mail the decision to your home address, and arrival dates will vary from M10 to a few days later. If the decision is a waitlist or a rejection, it’s just a thin envelope with a piece of paper in it. If the decision is an acceptance, the package is thicker as it includes various paperwork and information you will need to enroll (SOME schools send school swag too). We’ve received packages through FedEX, UPS, and USPS. Most of them came on M10 but a couple came on M11. In all cases, decisions were known on M10 via email or portal.
Funny. My son’s friend learned yesterday from a boarding school (his first choice) that he had been accepted. I wonder if certain schools can announce early. It is a school with learning supports. (I prefer not to name which one).
Only TSAO schools are bound to M10 (they came up with it). It’s a free-for-all for all other schools, but some follow TSAO’s lead.
I’m excited for M10 this year, too. ChoatieCorporal comes home for spring break on M10. I will probably not be hanging out on CC this year. 
Good luck to all of you!
Update: Milton
Decisions will be available via portal on M10 @ 7:00 am EST....
Credit to @cungen for the info 
Have fun @ChoatieMom 
I was told me an admissions rep that they made a pact through AISNE. Perhaps it was initiated by TSAO though.
From the Ten Schools website:
FYI. Westminster just emailed that decisions could be viewed via portal M10 at 6am
Gunnery: Decisions will be available on the portal M10 at 6 a.m. FA decisions will be mailed separately.
ok thanks! it’ll be so tough to wait until 5 pm @livesk8dream
Does anyone know if Westover is still only USPS parcel? It’s the only one I am not sure of online.
I have not heard of the M8 date posted here for NMH. All indications are M10.
Searched past threads… In the past it has been M10 (9:00 am)… I don’t know if it has changed in 4 years…
Did any applicants get an email?
I thought I read this somewhere but cannot locate it. I see that Exeter notifies by email at 6:00 am on M10. Does that include acceptance, rejection and waitlist? In other words, no matter the outcome, an email from Exeter should arrive…thanks
Last year NMH notified on M8, not sure what they will do this year.
@yearstogo
Yup all notifications (unless specifically said otherwise…i.e. mail for acceptances only) have you decision regardless of what it is…
NMH is M10 this year.
Anyone know for sure which schools sent packages via USPS last year? Not Fed Ex or UPS, but USPS?
@AppleNotFar @Atria @ninibuba NMH is 12:01 AM EST, M10, through their portal ~O) they sent an email a week or two ago