If you have a schedule where users are on-call every other week, you will need to create a layer within your schedule that reflects this type of rotation.
This schedule has 4 users. 2 of users are on-call during the weekdays. The other 2 are on call during the weekend. They rotate on a weekly basis.
Layer 1 will have my weekday rotations. User 1 and 2 will rotate on a weekly basis with a handoff time set for midnight on Monday.
Click Add Another Layer to create a second layer for weekend coverage. Layer 2 will has Users 3 and 4 on a weekly rotation. Their handoff time is Saturday at midnight. This rotation is restricted to the weekend.