Possible Clues:

• Person who renounces former belief or loyalty
• A station took in the traitor
• Heês changed his views in a Post Office report
• An Italian river region for a turncoat
• Renegade first of all rejected work, say
• Defector's worthless material, assuming a false role
• The traitor is a pilot officer, say
• Julian was such a mischief-maker hiding letters
• Religion repudiator
• Deserter, a naval man, say