Well, I'm a bit peculiar in that regard. I like to let every player get an introduction post in when the IC starts, but after that, it's largely free-ish, emphasis on the ISH.
Basically, especially in Advanced, I expect players to be able to determine when the appropriate time to post is. If you know you haven't posted in four days, you probably should unless you were the last one to do so in which case the momentum has slowed for some reason. Also due to the large cast, it's not natural to have to wait for 9 posts every time a character speaks to another - nothing would ever get finished that way or it'd be an RP full of only collabs lol.
After Rockette and I post, you guys are free to post when necessary. Obviously, I don't expect anyone to start their own little mini-RP with a bunch of NPCs inside of mine, but I'm sure you understand the picture. If Elton says something James, you're free to reply immediately and if we wish to have a longer scene with a longer conversation, we can collab so as not to initiate a back and forth in the thread. Don't misunderstand, I will and do regulate posting should it become wild or unsavory, but this method has worked for me for the most part in terms of character interaction.
When I move the RP forward, I usually say so everyone knows I'm not just posting a reply, but rather a scene moving post. Hope that answered your question :D.