What is happening:
The quest-giver for the Winter Wrap-up questline just... Doesn't exist. She isn't there. Ponyville/Ponydale is still very much covered in snow, and for some reason night doesn't appear to be ending?
What should be happening:
There should be a pony I can talk to to start the questline.
Steps to reproduce the issue:
Created a new unicorn character and completed their cutie-mark quest to completion. They are an adult in Ponyville.