(a) Up to seven days before the hearing, parties to an enforcement action may file supplemental or amended pleadings, so long as those pleadings do not operate as an unfair surprise to the opposite party. Amendments after that time will be at the discretion of the judge and may constitute grounds for a continuance.(b) The executive director may amend an enforcement petition to include changes in, but not limited to:(1) the amount of the penalty up to the maximum allowable by statute;(2) the violations alleged;(3) the number of days of occurrence of previously alleged violations; and(4) the injunctive relief (or remedial ordering provisions) sought.(c) The right to change the violations alleged includes the right to add causes of action based on any statutes within the commission's jurisdiction other than the one or ones upon which the executive director's preliminary report in the case was based.