BYMT waitlist stays open as long as they can possibly leave it. After second stage there may well be a third or even a fourth round of offers, but the majority of the movement does tend to be after the first stage/before second stage as people are often hanging on for NYMT results before making a decision on what to accept.
The plus side of the waitlist staying open is that it really does give people the best possible chance of a show, the downside is the waiting is agony ... I've been there and I know. Last year we went to late April before securing our final offer and that isn't unusual, as others on here have experienced the same. So sending you all of the positive vibes cause I know it can be tough.
Some people are fine with the waiting and others prefer to draw a hard line and withdraw from consideration after second stage come out. I get that the waiting isn't ideal for many who need to juggle calendars. I only have the one DC so its a bit easier for me, but I can completly understand why those with several DC needing answers on summer activities would find it extra hard.
Its worth bearing in mind that the waitlist times can vary massively depending on your DCs demographic and what spaces open up from declines/drop outs. Honestly it is completely impossible to speculate as to how or when you may get a waitlist offer other than it generally closes by end of April. Everyone will get an email when the waitlist closes to say no further offers will be sent. You can request your audition feedback at this point.
Finally my DDs very first experience with B/NYMT was a BYMT camp what will be four summers ago and I firmly credit that with being her first foot through the door if you will. I'll keep my fingers crossed that the waitlist is kind to you but its great that you do have the option of a camp which will be a fantastic experience. Plus if you do a camp with BYMT you also get to do the Christmas Concert Let It Snow which is a really good performance opportunity and great fun :)
Let us know how you get on!