Hi @Liam ,
As far as I know, tasks grouped by Category is not yet available in New Outlook. We understand how critical this feature is for many users like you. However, we assure you that we will be seeing this feature coming up soon in the New Outlook.
Our product development team is currently working on this feature. But currently there is no ETA as to when exactly the feature will be released and implemented on your device. Hence, we request you to keep your Outlook Office apps updated so that once the feature is released as a part of update it gets implemented on your device.
If any of those limitations are critical for your work, we recommend you stay in the Classic Outlook until they are resolved, or you can switch the toggle to go between apps as often as you want.
In addition, Microsoft To Do currently does not seem to provide the ability to set "Group by Category" as the default option. When you exit To Do and click back in, the tasks may no longer be grouped by category, and you may need to reselect "Group by Category".
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