Guruprasad குருபிரசாத் விஜயராவ்

As per rule, any one staying more than 180 days abroad has to convert their bank account to NRI account.  There are two types of NRI account

1. NRE – Non Residential External: Can deposit only foreign currency.  No tax on earned interest.
2. NRO – Non Residential Ordinary: Can deposit Indian, foreign currency, The interest earned in taxable.

Your account number can be retained same, which moving the SB to NRI account.
You can manage with out having NRE, NRO account as well.