Possible Clues:

• Erstwhile British booth
• Kent's changing situation -- 'smart' people no longer call here
• Hour in post office with bill, big beastly thing where fewer and fewer calls are made
• Pressure on Polish strike in old call centre
• Confined space where those inside call out
• Booth for making calls
• Once-ubiquitous red fixture seen along London streets
• Could hang this up for what one gets at Christmas from old call centre
• Booth for callers, red in the UK
• Vital pre-mobile communications facility?