When you are finished with your current lab, click on the reservation dropdown menu in the upper right and select “change exercise”.
You will be presented with the list of labs for the course. Select the next one that you want to work on.
The start time will be filled out already with the current time. The end time will be the same end time as you requested when you made your original reservation. These cannot be changed. Click “submit”.
Hit OK.
You will be taken back to the topology page. Clicking on the content button should give you the new PDF for the lab you just switched to. Your VMs will be in the same state you left them.