To upgrade to Silver or renew your membership, log into the Technology Partner Portal:
https://partners.adobe.com/exchangeprogram/experiencecloud.html
Click on the Benefits Center link in the top menu which should bring you to this page:
Click on the Silver Membership box:
Click Add to Cart. Click on your Shopping Cart:
Click Proceed to Checkout. You will then be invoiced for the Silver Membership and upgraded in our system.
If you have trouble logging into the Benefits Center, please reach out to Partner Support.