Possible Clues:

• "We're past the point of no return!"
• "Missed your chance"
• Bad news for a procrastinator, say
• 'Train's left the station!'
• 'Oops, missed the deadline'
• Carole King hit
• 'You missed your chance'
• Words of resignation
• "You had your chance"
• ''You snooze, you lose''