Utilize the 3rd party tool to speed up the process.
https://transactionpro.grsm.io/qbo
https://partners.saasant.com/affiliate/idevaffiliate.php?id=5051_2
1. Export the Check data you want to modify
2. Change the data (e.g the date in TxnDte column). Make sure not to change any data in the RefNumber and BankAccount.
3. Import the data back into QBO
The template should be like this
RefNumber | BankAccount | Vendor | PrintOnCheckName | TxnDate | Location | AddressLine1 | AddressLine2 | AddressLine3 | AddressLine4 | AddressCity | AddressState | AddressPostalCode | AddressCountry | PrivateNote | ToBePrinted | Currency | ExchangeRate | ExpenseAccount | ExpenseDesc | ExpenseAmount | ExpenseBillableStatus | ExpenseBillableEntity | ExpenseClass | LineItem | LineDesc | LineQty | LineUnitPrice | LineAmount | LineBillableStatus | LineBillableEntity | LineClass |
101 | Checking | Joe's Coffee | | 01/10/2020 | | 12 Main Street | Suite 102 | | | Albany | NY | 12345 | | | N | | | General Supplies | General Supplies | 85.21 | | | | | | | | | | | |
102 | Checking | Costco | | 01/10/2020 | | PO Box 1000 | | | | Dallas | TX | 28456 | | | N | | | General Supplies | General Supplies | 125 | | | | | | | | | | | |
103 | Checking | Property Mgmt Assoc | | 01/10/2020 | | PO Box 1800 | | | | Albany | NY | 12345 | | Mar 2011 Rent | N | | | Rent | Rent | 1000 | | | | | | | | | | | |
Hope it helps.