If you were offered a spot on the waiting list at UVA, you had a link to the Waiting List FAQs in your decision letter. I'm going to go over the parts that come up the most and add some more information. Feel free to ask questions in the comments.
How many people are on the waiting list?
We won't know this until May 1st. The waiting list forms as people hit the "accept" buttons under their letters in SIS. The Common Data Set, something every school fills out, covers the numbers. Every school publishes a Common Data Set, so you should be able to google and find these numbers for every institution.
From the 2015-2016 Common Data Set:
Do you have a policy of placing students on a waiting list? Yes
Number of qualified applicants offered a place on the waiting list: 4,547
Number accepting a place on the waiting list: 2,081
Number of wait-listed students admitted: 402
The waiting list will be big on May 1st because we need to ensure there are students to fit all ten sections of the first year class (Virginia and out-of-state students for each of the five schools/programs that take first years).
I accepted. Why are the buttons still there?
If you hit the "accept" button, you can always come back and pull yourself off the list. That is why the buttons remain after you opt in. There is no going back once you decline, though. If you decline the spot, the buttons disappear.
How many people will come off the waiting list?
Even though I've been doing this for years, I can't predict this one. May 1st is when all of the admitted students need to have deposits submitted to reserve a place in the Class of 2020. The class is supposed to be about 3,675 students. If we don't have that number of admitted students accepting a spot, we move to the waiting list.
It's hard to cite trends with certainty. One year, we might have room for in-state Nursing students and the next year, that group could be full on May 1. We're all waiting to see how this works out right now.
How many people got offers to come off the waiting list in the past?
Here's a decade of data, which should show you how unpredictable this part can be.
2013 - 185
2012 - 284
2011 - 117
2010 - 240
2009 - 288
2008 - 60
2007 - 159
2006 - 145
2005 - 83
How do I improve my chances of getting an offer?
There is a lot of conflicting information out there about this. Emailing a letter of interest to firstname.lastname@example.org is appropriate. Mailing a package is not. Updating us with significant news is okay. Bombarding every admission officer with an email each day is not. Please don't email one (or several) admission officers directly. We're just going to forward your email to email@example.com and it will take an extra day for the email to get filed. Save time and use the general account.
By the way, showing up in Peabody Hall will have no affect. I can't tell you how many students drive here and then sit on the sofa and ask the questions covered in the FAQs. This is not a good use of your time (or gas money!).
When/How do you make wait-list offers?
We start making waiting list offers as soon as we know we have space in the class. We move quickly because no one wants to drag this out. We aim to have everything wrapped up by the end of June. Last year, we completed the class on June 22nd. In 2014, we were done by June 6th. In 2013, we finished on June 3rd and the year before that, we were done on June 11th.
If you are going to get an offer, we'll call you at the number you put on your Common Application. The call is a heads up that your status is about to change in SIS. Of course, it's fine if you tell us "no thanks" and that's the end of it. We hope that people who are no longer interested in UVA use the "decline" button to remove their name from the list, but some people forget.
Anyway, the usual response is screaming or "OH MY GOSH!" When SIS updates, a new letter is viewable along with the buttons needed to accept the offer and pay a deposit.
Because we want to give students a few days to think about the offer (and because the Financial Aid folks need a day or two to post a package for the newly-admitted student), this process takes a while. I can't give constant updates on the blog. I can usually check in once or twice in May. I will always tell you when the Dean says the class is full.
What about aid?
If you applied for aid by March 1st and got all of your documentation in, Student Financial Services will put a financial aid package together. Once that's posted, you'll have a couple days to accept the offer and pay your deposit.
Look at your other options. Get excited about one of them and pay a deposit to guarantee yourself a spot in a freshman class somewhere.
By the way, calling a student and telling them that they are getting an offer of admission is probably the most exciting thing admission officers experience. We can't wait to make them and everyone has a story or two about favorite calls. I promise you that when it's time, we'll be working very quickly so we can deliver some happy news!