2A. Date of payment.— For the purposes of these rules, “date of payment” shall be the earlier of the dates on which the payment is entered in the books of accounts or is credited to the bank account of the person liable to pay tax:  Provided that —

(A)   the date of payment shall be the date of credit in the bank account when –

(i)     there is a change in effective rate of tax or when a service is taxed for the first time during the period between such entry in books of accounts and its credit in the bank account; and 

(ii)    the credit in the bank account is after four working days from the date when there is change in effective rate of tax or a service is taxed for the first time; and

(iii)   the payment is made by way of an instrument which is credited to a bank account,

(B)    if any rule requires determination of the time or date of payment received, the expression “date of  

            payment” shall be construed to mean such date on which the payment is received;