They have to be up to 180 acceptances by tomorrow though, so I am very confused.
That's not true. UNC has to have extended an amount of offers equal to the seats in their class. So by tomorrow, they need to have offered spots to 180 people but it doesn't matter whether those offers have been accepted yet or not.
AAMC Traffic Rules are very helpful: https://students-residents.aamc.org...ation-and-acceptance-protocols-admission-off/