73(1)Where a grievance or notice has been presented, filed or served by registered mail and the addressee claims that he has not received the grievance or notice, the person who presented, filed or served the grievance or notice may present, file or serve upon the addressee a second notice after he has ascertained that the first grievance or notice has not been received.

73(2)A second grievance or notice shall not be presented, filed or served more than one month after the day on which the first notice was mailed.

73(3)A second grievance or notice has the same force and effect for the purposes of this Regulation as the first grievance or notice would have had if it had been received by the addressee.