Changing approver on orders raised (but unapproved)

I am fairly new to Nav. There are a large number of queries where approvers are on holiday and orders are unapproved.
The current process is to change the approver in property user roles and also the service approval setup, but this is so time consuming and I cant see why the person who raised the order cant simply re-direct it to someone else.
Currently we have something called delegate, but if the approver is sick or on holiday, then how are they supposed to delegate? I would rather find out it is possible for the raiser to send to a different approver.
Can someone please advise?