In such cases time of supply will be

(i) where the invoice for the same has been issued and the payment is also received after the change in rate of tax, the time of supply shall be the date of receipt of payment or the date of issue of invoice, whichever is earlier; (However, for supply of goods payment of tax need to be made only at the time of issue of invoice in terms of notification 66/2017-Central Tax dated 15.11.2017) or

(ii) where the invoice has been issued prior to change in rate of tax but the payment is received after the change in rate of tax, the time of supply shall be the date of issue of invoice; or

(iii) where the payment is received before the change in rate of tax, but the invoice for the same has been issued after the change in rate of tax, the time of supply shall be the date of receipt of payment; (However for supply of goods payment of tax need to be made only at the time of issue of invoice in terms of notification 66/2017-Central Tax dated 15.11.2017)