Circular reference error when swapping two consecutive users in a shift rotation

Problem

We have a team of four people. Two members want to swap their on-call schedule for one week, but when a temporary absence is configured it causes a circular reference error. Why is this happening?

Environment

All versions of xMatters

Resolution 

This message you're seeing is an expected behavior as the schedule would create a circular reference. Temporary absences should only be used for configuring a user absence (not a shift swap). In this situation, you're telling the system that User A will be absent and User B will be replacing them, but at the same time User B will be absent and User A will be replacing them. 

To solve this issue, the best approach would be to create a one-off shift where User A and User B swap positions. To learn more about creating shifts, see Schedule shifts.

In this example, we've created a one-off shift that has the same start and end time as the original recurring shift:

Right now, both shifts will be targeted for notifications. As we only want the one-off shift to be targeted, the occurrence date for the original recurring shift needs to be set to start immediately after the end date of the one-off shift:

Now the changes have been saved, only the one-off shift is available and will be targeted for alerts:

When the one-off shift has ended, the original recurring shift will continue as scheduled.