So that External Exams works in multi-divisional systems, the Departments and Subjects need to be shared across divisions. This means that HoS at one division can access the HoS reporting of another division, and also that HoS/HoD of all divisions are included whenticking the HoD/HoS box in 'Contact Pupils' Teachers'.
Ideally we need a way to allocate a HoD to a single division in Teaching Manager - as the division they're set to in HR Manager doesn't prevent this happening.