What does the second wave summer internship process actually look like?

Just had a superday before the weekend and it’s been something that I’ve wondered. The bank I specifically applied to sent me through a second wave “Referrals only” portal that I ultimately received a first and final round interview for. Got referred by an MD who’s an alum from my school who told me it’s just to fill extra spots that were available from offer deniers in the main wave.
 

The process has been peculiar in that the senior recruiter that has been in communication with us literally gave us the dates of potential superdays before we had even heard back from the first round. We were supposed to let them know of our schedule because “the more flexible the better”. Then superday decisions were released a day later.
 

It seems pretty insensitive to send this out, considering I’m not sure how 1 day of schedule notice was ever going to mean much. Right from the get-go, I’ve sort of been under the impression that this has all been more out of principle and just to make sure we’re not completely clueless. That whoever is currently still in this process were guaranteed spots by whoever referred them. Based off of the wording of the recruiter, I can’t tell if there’s 3 people, 30 people, or 300 people in this second wave.
 

What is the nature and scale of “Second wave” hiring in the banking world? How unserious or serious is this process on the inside? Do I have a 100% chance of getting the offer or 0%? Because that’s what it currently feels like to me.