Possible Clues:

• Airline supplier?
• London theatre best for the likes of 1 and 5 31
• Writer of words for a song
• He writes the words first, apparently
• Songwriter left good man to keep younger company
• He writes words for songs
• Person who writes the words for songs
• Sit Cyril down - he's a songwriter
• Musical words writer
• One who writes the words of a song