Hello Will Drotar,
Thank you for reaching out to Microsoft Support!
As for your problem, we conducted a test, after creating a plan through the Graph API, the newly created plan cannot be seen in "My Plans" in the browser. After refreshing the page and expanding the list through show more, the newly created plan can be found below, and the test results are as follows:
It is recommended that you refresh "My Plans" in your browser after creating the plan through the Graph API.
Hope this helps.
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