This discussion clarifies the rules around shifting purchase invoices between months. Generally, you cannot shift a March invoice to April if the goods were received or services rendered in March. However, if the goods or services were not fully provided until April, the invoice can be booked in April. The key factor for claiming Input Tax Credit (ITC) is the actual receipt of goods or completion of services.
Just had asked a Q of shifting March Purchase invoice in april, i had received answer "NO", but if bill is still not done then in that case can we shift.
11 April 2020
The law says that unless you receive the goods you cannot book the invoice as purchase and claim ITC. Therefore, if the goods received in April you can book the purchase in April.