We are using different projects for our Tier 1 and Tier 2 support teams. Most software issues come directly to the Tier 2 project, but some issues spend time with the Tier 1 group first and get escalated to Tier 2. When this happens the issue in the Tier 1 project is closed and a new linked issue is opened in the Tier 2 project.
Form the customer's perspective the SLA for 'time to resolution' should cover the total time the issue spent in both projects. Is there any way that we can add the time spent on the Tier 1 issue to the Tier 2 issue when it is opened in order to accurately calculate and track the total time to resolution SLA?