The challenge timeline provides the all details of the challenge stages.
You'll receive email notifications when important actions need to be taken. Make sure you are able to receive them and always check on SPAM for missing ones.
By clicking one of the stages on the timeline you'll be able to see all the applications that made it to that stage.
If you have any further doubts, access the challenge community and leave you message on the support channel. You can access the community by clicking on the "Join the community" button, right below the timeline.