Omnicron already existed in July...
https://www.weforum.org/agenda/2021/07/how-scientists-detect-new-covid-19-variants/
How scientists detect a new COVID variant | World Economic Forum
As a new COVID variant is discovered, here’s how scientists track down new strains as the COVID virus mutates, with potentially higher risks to health.
https://www.weforum.org/agenda/2021/07/how-scientists-detect-new-covid-19-variants/