GSTR9 table 10 explanation

It is for details which pertains to the year for which filing is being done but filing were done in subsequent year's monthly returns

As per law you can show the supplies till you file the next financial year September return or annual return (GSTR 9) of current financial year. Table 10 refers to the such Supplies/tax which you have declared in subsequent financial year before filing of September return or annual return. This also includes amendments and debit notes made in the previous year invoices. Also please note these are such values which has increased the liability. If the liability is decreased then you need to show it in Table 11.