Source: – True Indology / Twitter.
2) The script used by early Sikhs was Gurmukhi. Gurmukhi is a script born from Sharada. Sharada is the script of Kashmiri Pandits. This is how the Omkara is written in Sharada script.
What was simply Omkar in early Gurmukhi was understood as "Ek Omkar" after the script evolved pic.twitter.com/sNr06J1hKc
— True Indology (@TrueIndology) November 23, 2018
3) The definitive evidence of this hypothesis comes from Gurharsahai Pothi. This is one of the earliest manuscripts of Guru Granth Sahib and was in possession of descendants of Guru.
In the Pothi, the Mulmantra has Omkar and not "Ek Omkar" pic.twitter.com/rpvN318WEO
— True Indology (@TrueIndology) November 23, 2018