Hello,

You must be aware that this year due to covid pandemic there has been delay in the admission cycle of various courses, hence there are greater chances of impact  on the schedule of next year, for all the universities you mentioned as of now there hasn't been any official notification released by the concerning authorities for the commencement of registration process or even exam dates for that matter, you can stay updated at the official website of the mentioned universities such as-

BHU @ http://bhuonline.in/

Allahabad University @ https://www.allduniv.ac.in/

Lucknow University @ https://www.lkouniv.ac.in/

You can also follow our site for any latest updates regarding application form, paper pattern, syllabus, previous year paper, entrance test dates and other such relevant details,