If you edit or make any changes to transactions (Sales invoices/Purchase receipts/Bank transactions/Journals) in your account that were issued and submitted in a previous VAT period, Tally will pick these changes and include them in your next VAT returns.

For example, if any changes are made to invoices that were included in Q/E July VAT returns, the new changes made will be flagged, picked up and included in your next VAT returns for Q/E October.