(1) Prior to the assignment of a presiding officer the initiating document may be amended at any time.

(2) After the assignment of a presiding officer the initiating document may be amended upon motion filed by the department and service to all parties. The motion will be granted unless the presiding officer finds a party will be unduly prejudiced or burdened.

(3) When the initiating document is a statement of charges, a party must submit an answer within thirty days.

(4) The presiding officer may delay all or part of the hearing if necessary to afford a party the opportunity to respond or prepare.