Atlassian Clover is now available as an open-source project. Effective April 11, 2017 Clover is no longer available for purchase or renewal. 

Question Answer
I still have active maintenance on Clover, how does the open sourcing effect me?

Official support for the latest release of Clover (4.1.2) will end on April 11, 2018. If your maintenance period ends after this date, you can expect to receive a refund equal to the time period extending beyond April 11, 2018.

Keep in mind that all Clover licenses are perpetual, which means you can use the last release for as long as you'd like. However in the future you might consider using the open-source version prepared by the community to access new features.

Can I still renew or upgrade Clover?

Renewals and upgrades of Clover are no longer available effective April 11, 2017. If you require an upgrade to a different license tier we recommend switching to the open-source version. Open-source Clover does not require a license tier and offers unlimited usage.

Clover source code is available for download at https://bitbucket.org/atlassian/clover. To begin running Clover as open source, you'll need to clone and compile locally. Open-source documentation for Clover is available here https://atlassian-docs.bitbucket.io/.

I switched to the open-source version of Clover but still have active maintenance on my old license. Can I receive support?

Atlassian support is only valid for the licensed version of Clover. Official support for the latest Clover release (4.1.2) will end on April 11, 2018.
When will Atlassian stop supporting Clover? Official support for our last release of Clover (4.1.2) will end April 11, 2018.
I have a Clover license, do I need to migrate to another tool?

No migration is required. Please bear in mind that license keys issued by Atlassian are perpetual, so you can use Clover as long as you want.

However, you may want to consider using the open-source version prepared by the community (if any are released) to get new features.