@HotCakeX - Thank you for reporting this issue. This was partially by design*. However, the policy template should be updated weekly similar to the Dev channel browser release cadence. I've reported the issue and we are working to get it resolved as quickly as possible.
* Why by design?Browser policies apply to all channels. If you set a browser policy it will effect Canary, Dev, and Beta if the associated feature has reached the channel. The are a couple of exceptions in the update polices. For example, Allow installation can be configured per channel.
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HotCakeX (Esteemed Contributor)