"Extended benefit period" means a period which
(1) Begins with the third week after a week for which there is a state "on" indicator; and
(2) Ends with either of the following weeks, whichever occurs later:
(a) The third week after the first week for which there is a state "off" indicator.
(b) The thirteenth consecutive week of such period. No extended benefit period may begin by reason of a state "on" indicator before the fourteenth week following the end of a prior extended benefit period which was in effect with respect to this State.