Possible Clues:

• Unrelenting over bowled, say, keeping in
• Like mules popular in outside broadcast, say
• Stubborn old boy elected in republic?
• Stubborn old boys can have had a meal
• Unwilling to budge
• Stubborn old beast in a frenzy swallows can
• Olga's beginning summer time at home worried stiff?
• Stubborn stain to be removed
• Female bird
• Stub, born like this?