This circular letter is to highlight a Corrigendum to EN 50136-2:2013+A1:2023 dated 30th November 2023. At the time of writing, NSI Technical Bulletin No. 0064 did not take this Corrigendum into account. Consequently, the implementation date stated was incorrect. The Corrigendum made to EN 50136-2:2013 on 30th November 2023 changes the implementation date of Amendment 1 to 13th February 2026. NSI Technical Bulletin No. 0064 rev1 reflects this. If you have any questions or queries regarding these changes, please do not hesitate to contact me.