In January 2017, we announced some changes to the Gmail routing settings in the Admin console. For technical reasons, some of these changes were delayed past the originally communicated date and are now launching this month.
Convert old Gmail routing settings now
Going forward, your remaining Sending routing, Receiving routing, Catch-all address, and Domain-level routing settings are read-only. These settings are still active, but in order to make changes, you need to click the CONVERT button next to the existing rule.
Once you click CONVERT, we’ll convert the setting and map it to the new fields automatically. The converted setting will then be placed in the unified routing section, where all of your rules will be manageable from one place. The old setting will no longer be visible in the user interface, so you won’t need to clean up old rules afterwards.
All settings automatically migrated starting July 11th
If you don’t convert your settings using the CONVERT button, they’ll be automatically migrated to the unified routing section no earlier than July 11th, 2018. This migration will take place over the course of several weeks.
CONVERT button launching to both Rapid Release and Scheduled Release now
Automatic migration starting for both Rapid Release and Scheduled Release no earlier than July 11th, 2018
Available to all G Suite editions
CONVERT button: Full rollout (1–3 days for feature visibility)
Automatic migration: Extended rollout (potentially longer than 15 days for feature visibility)
Reference by Google.com