The default sort order on the mobile device is "Last name, first name". In order to be compatible with Pocket Outlook, BirdieSync enable by default an option to automatically generate a "display name" as "Last name, first name". However if you prefer to have your contacts sorted with "First name, last name", simply unselect the option 'Fill Pocket Outlook "Display Name" field with "Last name, First name" or "Company name' in menu "Tools/BirdieSync/Options...", Contact panel and Miscellaneous tab.