An SLA Profile/Policy is very simple. To set up your first SLA policy:
Don’t forget to click the UPDATE or PUBLISH button in order to save the alerts.
The target time is always specified in minutes and there is a handy calculator that helps you convert hours and days into minutes.
Simply enter the amount of hours or days and then select HOURS or DAYS from the drop-down. The number of minutes will be shown. You can then click the SET TARGET TIME link to populate the TARGET TIME field above the calculator.
If you change the TARGET TIME of an SLA POLICY then you probably want to recalculate the due dates on any tickets that might have that SLA policy attached to it. Just click the RECALCULATE DUE DATES button on the right of the SLA profile to fire off this process.
Only due dates for open tickets will be calculated. But, even so, this could take a long time to complete! You might need to make sure that your Web Host allow you to have long running scripts otherwise the recalculation process will not complete!