Ok good deal. Thanks, eprman.

In the App Transactions tab, you should be given the option to review, add, exclude, and undo any Square transactions. In this instance, I recommend undoing the transactions with the incorrect dates. You can then make any corrections and then re-add them to QuickBooks. It's always a good idea to chat with your accountant before completing these types of actions within your account. 

There are more details about the App Transactions tab and how Square works with QuickBooks in this link: Connect to Square

You know where to find me if you have any other questions!