Possible Clues:

• Counter
• Forestall ex-pupil by way of a note
• Get round, being above it
• Anticipate
• 'Oh, be by way of starting to be unnecessary (7)'
• Prevent
• Get rid of old boy having had tea maybe around six
• Remove award that's outstanding by way of threats, primarily
• Do away with building above it
• Forestall old boy through note