I don't know of any group for dance prep, you could try asking the North staff - north@oakdance.org The address is 9356 Graton Road, Graton, CA See the booklet for directions. It is on the home page about half way down. Click the link:  2025 Northern California Dance Booklet.

There is a picture in the blog post titled “Changes”. And here is a more recent picture.

Edited response: Since my initial reply to this issue I have gone back to review what it would take to add a history page. I had forgotten I had done a lot of initial work putting together the structure needed. Adding some final touches to the structure, then adding content, has resulted in a new history page. You can access it by clicking on the Dance/Dance History menu item. Or click here.