It is very helpful that Microsoft makes a 'Canary Tenant' available to test existing solutions with upcoming changes to the platform. This helps us to catch potential breaking changes early.

However, it turns out that only new functionality is rolled out to the Canary Tenant, not other changes. For example this caused major problems with our customers when Code Based sand-boxed solutions were discontinued without adequate warning (other than a general announcement a couple of years earlier without a specific date).

Please roll out ALL non-emergency changes to the Canary Tenant before rolling them out globally.