Or they'll force customers to buy new connection with this phone of ₹500 or above
Jio SIM Card is mandatory in one of the sim slot. So, one can't use other companies 4G services in this handset.
What do you mean by one of the SIM slot ? Jio sim cannot be used in 2nd slot as it is 2G only and I am sure 1st slot will support backend compatibility with 2G also as it support 4G VoLte so running two 2G SIM will not be a problem I think