There can be multiple firing locations for all these fuels in a calciner It depends on the design of the calciner.
Calcination should only occur in the bottom two stages of the preheater. However, the preheater cyclones do not have 100% collection efficiency so some calciner material migrates upthe preheater. How much depends on the efficiency of each preheater cyclone stage, but 1% in the top stage, 5% in the second stage, 15% in the third stage, 30% in the fourth stage and then 95% in the fifth stage after the calciner would not be unusual.
Dr Michael Clark