Updating Your Imported List of Properties
Every time you import a list of properties, Pebble will check to see if the property already exists in your Pebble account. It checks the county and APN (Assessor's Parcel Number) of the property in the import list against those already connected to Pebble.
In this article:
Importing List
To update a list go to Campaigns in the left sidebar menu and select your campaign.
Click on Import List in the top right corner.

Type in the county name and select the correct one from the dropdown menu.
You can drag and drop or browse to select the file and then click Upload.

Map the fields you'd like to bring in. At this stage, you can even bring in fields you didn't bring when you first imported the list.

Once the list of properties has been uploaded, Pebble will check to see if that property already exists in your Pebble account. This means that any additional property information will be added to the existing property, preventing duplicate listings.
Careful! In order for Pebble to not duplicate any properties, do not change the APN number that was first imported.