It would be useful if there was a next reply time SLA.
Currently the timing on the SLA types all run from when a ticket enters the system.
It would be helpful though if you could , for example, set a first reply time of 1 hour and then a next reply time of 6 hours.
So when a ticket is created the agent has an hour to send the initial response.
If the user then responds the agent has six hours to send his next response.
If the user then responds again the timer is reset so the agent has another six hours to send that response and so on.