I believe you can change the view of the calendar from month day week.
I agree, you should be able to change it. Most of the time, the options in the upper right or left hand corner to switch views, but it could be different. Also, we do have an Official Android 9.0 Pie Discussion Thread where we're discussing the update, giving feedback, as well as folks offering help. Please join that conversation if you'd like to chat more about it.
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