It's the last day to submit a talk to the #37C3:

https://content.events.ccc.de/cfp/37c3/index.en.html

Submission is open until 23:59 UTC. And they've also opened assembly registration (until December 3rd):

https://events.ccc.de/en/2023/11/10/37c3-call-for-assemblies/

No news about ticket pre-sale yet.

In case you miss the 37C3 deadline, you still have a week to submit something to #FireShonks23:

https://pretalx.c3voc.de/fireshonks23/cfp