"Where the matters under the main clause are modified due to reasons prescribed by Presidential Decree, such as changes, etc. of collective agreements or rules of employment" in the proviso of Article 17 (2) of the Act means any of the following cases: <Amended on Mar. 30, 2021>
1. Where they are modified by written agreement under Articles 51 (2), 51-2 (1), proviso of paragraph (2) of that Article, and proviso of paragraph (5) of that Article, 52 (1), proviso of paragraph (2) 1 of that Article, 53 (3), proviso of Article 55 (2), 57, 58 (2) and (3), 59 (1), or 62 of the Act;
2. Where they are modified by employment rules under Article 93 of the Act;
3. Where they are modified by collective agreements under Article 31 (1) of the Trade Union and Labor Relations Adjustment Act;
4. Where they are modified by statutes or regulations.[This Article Newly Inserted on Sep. 22, 2011][Presidential Decree No. 31584 (Mar. 30, 2021) The part regarding Article 53 (3) of the amended provision of subparagraph 1 of this Article shall be effective until December 31, 2022 pursuant to Article 2 of the Addenda][Enforcement Date] The following parts of the amended provisions of subparagraph 1 of Article 8-2: The dates specified as follows:(a) Part of a business or business place with a regular workforce of not less than five but not more than 50 employees, as part of Article 51-2 (1) of the Act, the proviso of paragraph (2) of that Article and proviso of paragraph (5) of that Article, Article 52 (1) and the proviso of paragraph (2) 1 of that Article: July 1, 2021;(b) Part of Article 53 (3) of the Act: July 1, 2021;(c) Part of a business or business place with a regular workforce of not less than five but not more than 30 employees as part of the proviso of Article 55 (2) of the Act: January 1, 2022.