CMHC 23 hour observation

I am new to behavioral health coding and have a couple of questions if someone can help me.
The CMHC is opening a 23 observation unit and do you know which Medicare codes I can review, if they are billed on a UB-04 and if so what would the revenue code be?
Any help and direction would be great! Thank you ahead of time. I can also be contacted at whentermoon@gmail.com

CMHC 23 hour observation