Hello Aspirant,

Based on the current COVID-19 situation , with delay in the conduction of several examinations and  general academic calendar , chances are there that JEE 2021 January session might be postponed . But nothing can be said for sure due to the high level of uncertainty prevailing now as far as the education sector is concerned . Hence , you need to keep preparing and not depend on assumptions.

You may refer this article below where NTA Director, Mr.Vineet Joshi talks about this:

https://engineering.careers360.com/articles/will-there-be-any-delay-in-jee-main-2021-january-exam

Hope this helps.