(1) A party on whose behalf a subpoena was issued may give written notice to the person to whom the subpoena is directed of a date or time later than the date or time stated in the subpoena as the date or time to do either or both of the following—(a) attend to give evidence;(b) produce a document or thing.
(2) If notice is given under subrule (1) , the subpoena has effect as if the date or time stated in the notice were the date or time stated in the subpoena.