Unless the court orders otherwise, the parties may by written stipulation
(a) Provide that depositions may be taken before any person, at any time or place, upon any notice, and in any manner and when so taken may be used like other depositions, and
(b) Modify the procedure provided by these rules for other methods of discovery, except that stipulations extending the time provided in R. 4:17 (interrogatories to parties) may be made only with the approval of the court.