In calculating the period for a claim for a retirement allowance, etc. or a claim for a refund of premiums or past service premiums, if the claim is made by mail or by correspondence delivery prescribed in Article 2, paragraph (2) of the Act on Correspondence Delivery by Private Business Operators (Act No. 99 of 2002) provided by a general correspondence delivery operator prescribed in paragraph (6) of that Article or a specified correspondence delivery operator prescribed in paragraph (9) of that Article, the number of days required for sending is not counted in that period.
退職金等の請求又は掛金若しくは過去勤務掛金の返還の請求に係る期間を計算する場合において、その請求が郵便又は民間事業者による信書の送達に関する法律（平成十四年法律第九十九号）第二条第六項に規定する一般信書便事業者若しくは同条第九項に規定する特定信書便事業者による同条第二項に規定する信書便により行われたものであるときは、送付に要した日数は、その期間に算入しない。
Read this with the articles around it
retirement allowance, etc.machine translation
「退職金等」
A retirement allowance (退職金) or a cancellation refund (解約手当金).
Short name set inArticle 8, paragraph (2), item (iii)