When Microsoft releases an update to Dynamics 365, such as a CRM Update Rollup, thorough testing is required before the update is installed in a production environment. To allow adequate time for testing, it is recommended that CRM Update Rollups should not be applied for 30 days after release.
Many CRM environments include customized functionality. To reduce the risk of downtime and ensure a smooth transition, it is recommended that you test each CRM Rollup in a development or test environment to ensure that your customizations are not impacted by changes implemented in the rollup.