The edit page allows maps to be updated with additional addresses quickly. Drag and drop (or copy/paste) the modified spreadsheet on the edit page.
The edit page for premium & pro users can be found on the MyMaps page (https://www.easymapmaker.com/account/MyMaps ).
For regular users, an url is provided to the edit page in an email that gets sent when the map is saved.
For more information on adding data to the edit page see https://www.easymapmaker.com/support/add-data-on-the-edit-page/