Hi Jonathan,
If you import a statement using our own import tool and the statement is overlapping with another you have previously imported, the system will display a warning message as soon as you have imported.
What I would like to happen is for the system to then suggest which transactions are overlapping and offer to delete them for you.
Unfortunately this doesn't happen at the moment so you will have to manually remove the transactions that are overlapping from the imported statement by clicking on the Narrow Results link -
The system will then show you the statement you have just imported at the top, a Narrow down option in the middle and a list of all your previously imported statements at the bottom.
Use the Narrow down date range to select a range of dates not including the overlapping transactions so for example from the screenshots if I had already explained the 1st and 2nd of September I would select 3rd Novemeber to the end date. Hit the Narrow Results button to work its magic.