The offer begins on December 15, 2020 and ends June 30, 2021, or once all 7,000rewards have been distributed; whichever occurs first (the “Term”). Developers residing in the United States that are 18 years or older who have successfully completed Cloud Skills Challenge* during the Term will be able to receive one (1) exam voucher redeemable for one free eligible Microsoft Certification exam (valued at $165)

https://learncloudchallengeapp.blob.core.windows.net/sharedfiles/tc_mo_certification_offer_dec20_final.pdf

https://www.microsoft.com/en-us/us-partner-blog/2020/10/05/sharpen-your-teams-technical-skills-with-the-cloud-skills-challenge/