Have a look to my 'call-sign', I've enjoyed so many of them
In my previous job (Night ops Cargo operator, 30 aircrafts, Hub and spoke, Officer-Dispatcher-Controller-duty manager), decision is for the Duty manager except during week-ends when the Controller can charter well-known carriers with pre-agreed arrangements if required.
In my current job (Bizz jets, 15 aircrafts, worlwide ops, Dispatcher-duty manager), decision is always for the duty manager (on call during nights).