Difference between Response and Resolve in SLA?

I’m not totally clear on the difference between Response and Resolve time in the SLA config. The docs say You can define both "Response" and "Resolve" and RT will pick the one that comes earlier as the Due date.

How do I define a “time to first response” vs a time to reply once a customer has been engaged?

Set( %ServiceAgreements, (
    Default => '3 Business Days',
    Levels => {
        '3 Business Days' => {
            Starts => { RealMinutes => 0 },
            Resolve => { BusinessMinutes => 60*8*3
            Response => { BusinessMinutes => 60*8 },
            BusinessHours => 'Default',
        },
    },
));

The above sets the due date to 3 business days on create. When I reply the due date is unchanged instead of being unset. With just Response defined the due date is unset on reply the way I would expect.

As far as I know, it doesn’t matter if it’s the first or last response sent from the user. It’s the same SLA.

So, there is only two SLA indicators: time to respond and time to resolve.

Unluckily, RT doesn’t have a sophisticated SLA management, it’s very simple.

Remember: run rt-crontool every x minutes on those tickets whose SLA need to be reviewed (new, open, etc.).