Possible Clues:

• Journalist going round library, organised one up at dawn
• The worm catcher
• Journalist circling library aimlessly - he's arrived before time
• Derby rail works being the first to start in the morning
• One dealing with matters arising sooner?
• Dawn on one?
• 'The ..... .... catches the worm'
• Might be in the 23 down, but not of late
• One who rises before others
• … am person ultimately prone to uncontrolled ribaldry