3.  Once the file has been transmitted to the arbitrator, the parties shall send directly to him all pleadings and written statements (if there are more than one arbitrator, the transmission shall be made directly to each one of them), with a copy thereof to the other party and to the Secretariat. The arbitrator shall send to the Secretariat a copy of his communications to the parties and to other persons.
4.  The transmission of the petition for urgent measures is governed by the provisions of Article 8.
5.  The communications of the parties, the Court, the Secretariat and the arbitrator are validly made if they are delivered against receipt or if they are sent by registered mail with a return receipt or by equivalent means, including transmission by private courier. The time-limits provided for in these Rules shall run [from] the date of transmission.

Article 10 TIME-LIMITS

The time-limits provided for in these Rules can be extended by the Court or by the Secretariat, on their own initiative or following a reasoned petition of the party or the arbitrator.