Possible Clues:

• Fare thee well!
• Brest 'Bye!'
• French word for farewell
• Some say it when leaving university with a pass
• Later aid compromised by European Union
• Won't live in gold until we meet again
• Farewell, on the Riviera
• "Bye-bye, Brigitte"
• Languish in a posh 14
• A long universal farewell