Possible Clues:

• Surprising strategy
• Jump when hospital accepts doctor ahead of university
• Surprise as foot's first amputated at hospital
• Some British submarines set up and spring a trap
• Await and intercept unexpectedly
• Weakening
• Lie in wait; trap
• Unexpected attack prior to PM joining President
• Lying in wait
• Lie-in? Wait for transport after morning at hotel!