My 2005 UK Peugeot Service booklets simply say "your Peugeot dealer will advise you of the replacement interval". Other sources suggest that the cam belt should be changed as below: (whichever comes first and note that almost all 1007's are now over ten years old)
normal use: before 75,000 miles (120,000km) or ten years
arduous use: before 55,000 miles (90,000km) or five years
normal use: before 150,000 miles (240,000km) or ten years
arduous use: before 110,000 miles (180,000km) or five years
Peugeot define "arduous use" as "repeated short journeys" and "town use" Their full list is in the Maintenance Record book
I have heard of several cases of 1007 belts failing between 70,000-80,000 miles: be aware that the actual failure may have been initiated by failure of the idler pulleys or water pump.