16. Several cases before the board pertaining to the same issues or whose matters could suitably be joined, whether or not the same persons are involved, may be dealt with at the same time and decided on the same information or documents as decided by the board on its own initiative or following a request by an interested person. The board may also decide that a case is to be dealt with first, the others remaining suspended until a decision is made on the first case. The board may also decide that a case is to be heard by preference.