Shromani Gurdwara Parbandhak Committee decided to implement the new Reformed Nanakshahi Calendar from 1999 CE. The changes were recommended by the Calendar Reform Committee under the aegis of The Institute of Sikh Studies, Chandigarh. In this article these changes and why they were necessary are discussed. The SGPC General House passed a resolution to implement the calendar.
Pal Singh Purewal, introduced the term Mool (original) Nanakshahi Calendar in 2017, which refers to the pre-altered version of the calendar introduced and first accepted in 1999 which permanently synchronized Mool Nanakshahi (religious) Calendar with Common Era (CE) Calendar. 
Significant resolutions were adopted at the Chicago conference in December 2017. More importantly 3 dates were fixed for the upcoming years so that the Nanak’s Gurpurab, Bandee Chorrd Divas, and Holla-Muhalla fall on the same date each year. The fixed dates, in addition to the already constant Vaisakhi April 14th date, are: