(a) Except as otherwise specifically provided in subdivision (a) of Section 30602, any appealable action on a coastal development permit or claim of exemption for any development by a local government or port governing body may be appealed to the commission by an applicant, any aggrieved person, or any two members of the commission. The commission may approve, modify, or deny such proposed development, and if no action is taken within the time limit specified in Sections 30621 and 30622, the decision of the local government or port governing body, as the case may be, shall become final, unless the time limit in Section 30621 or 30622 is waived by the applicant.
(b) The commission shall hear an appeal unless it determines the following:
(1) With respect to appeals pursuant to subdivision (a) of Section 30602, that no substantial issue exists as to conformity with Chapter 3 (commencing with Section 30200).
(2) With respect to appeals to the commission after certification of a local coastal program, that no substantial issue exists with respect to the grounds on which an appeal has been filed pursuant to Section 30603.
(3) With respect to appeals to the commission after certification of a port master plan, that no substantial issue exists as to conformity with the certified port master plan.
(c) Decisions of the commission, where applicable, shall guide local governments or port governing bodies in their future actions under this division.