I have registered to databricks DAIS 2025 website. I could over 700+ virtual sessions. Some are having dates and time but some are not. Also i dont see any register button on the sessions. I am interested in below sessions , How to register for these and how do i know when they will start:

What's New With Databricks and AI
What’s New in Unity Catalog With Live Demos
Introducing Lakeflow: The Future of Data Engineering on Databricks