(a) A grievance concerning a continuing practice or condition may be presented at any time if its adverse effect is presently continuing. Documents contained in official employee personnel files, for example, shall be deemed to constitute a continuing condition.

(b) Subject to paragraph (a) of this section, a grievance under these regulations is forever barred, and the Grievance Board shall not consider or resolve the grievance, unless the grievance is presented within a period of 3 years after the occurrence or occurrences giving rise to the grievance, except that if the grievance arose earlier than 2 years prior to the effective date of these regulations, the grievance shall be so barred, and no considered and resolved, unless it is presented within a period of 2 years after the effective date of these regulations, There shall be excluded from the computation of any such period any time during which the grievant was unaware of the grounds which are the basis of the grievance and could not have discovered such grounds if the grievant had exercised, as determined by the Grievance Board, reasonable diligence.

(c) A grievance shall be deemed presented to the responsible official (§ 16.7(b)), transmitted to post or bureau (§ 16.7(c)) submitted for agency review (§ 16.8) or filed with the Grievance Board § 16.11(a):

(1) On the date of its dispatch by telegram, registered or certified mail, or receipted mail, in a diplomatic pouch;

(2) On the date of its arrival at the appropriate office, if delivered by any other means.