Should I switch from my current company to Tech Mahindra or not

I am having 3.4 years of experience as SAP ABAP+TM technical consultant in Accenture with 6.5 LPA CTC and I have an offer from Tech Mahindra with 11 LPA fixed. My notice period will be 90 days.

My manager told me that they will give me promotion in Accenture to level-10 in June cycle.(Not sure if there will be any change in promotion cycle as it happened in last year)

Can you give me some insights if I should switch to Tech Mahindra or should I stay in Accenture?

And is the salary offered by tech Mahindra is fine according to market standards?