Changes to custom retention policies in Mattermost 9.2

Applies to Enterprise Edition only.

Starting with Mattermost v9.2, we're changing how custom data retention policies are being handled when no global retention policy has been set. Until this version, custom policies would only be executed if a retention run was kicked off manually using the System Console. 

As this conflicted with the language in the product interface that allowed an admin to specify a specific cadence when to run the retention job, we changed the behavior to enable custom retention jobs to run independently from the global retention policy.

This new behavior would, for example, allow you to periodically clean a channel's or team's messages without a global data retention policy being enabled.

If any custom data retention policies are enabled in your System Console, please double-check their validity before upgrading to Mattermost v9.2. After this upgrade, all retention policies will be run at their set cadence regardless of a global retention policy.