Immunity under section 270AA depends on tax payment, no appeal, and timely application for penalty and prosecution protection. Immunity under section 270AA is available to an assessee who pays the assessed tax and interest within the demand period, does not file an appeal, and applies in the prescribed form within one month from the end of the month in which the relevant order is received. Where penalty arises from under-reporting under section 270A(9), payment of 100% of the tax on under-reported income as additional income-tax is required. Immunity covers waiver of penalty under section 270A and protection from prosecution under sections 276C and 276CC, subject to the bar where proceedings under Chapter XXII have already been initiated.