I know Aaron Tveit is on vacation from the end of February until some time in early March - another recent thread touched upon this so check that for exact dates. The website also reflects this- if you try to go and buy tickets during his vacation, it will say he is out. Besides that, I believe he is in every show. Aaron's fan base recently has noted that he beat his own record of "most shows performed in a row" beating his attendance record for Catch Me If You Can.
On Ricky Rojas's Instagram live yesterday, Danny joined and fans were asking when he would be back. Danny said the 21st, so I assume he meant he'd be back January 21st.
Not sure about others 
~E