The new guideline applies to all EGCS installations which are delivered to vessels or are significantly modified on or after 1 June 2022. For EGCS installations with a documented contractual delivery date prior to 1 June 2022, but where delivery was delayed due to the pandemic situation, for instance, the MEPC.259(68) guideline may still be applied. https://www.dnv.com/news/updates-to-the-2021-guidelines-for-exhaust-gas-cleaning-systems-scrubber-guideline--223492