Hello Michael Garwood,
Thanks for your question.
Yes, you are correct. You can create a Maintenance Configuration with the schedule, including the date and time for the one-time deployment.
If repeats is set to 0, there is no recurring schedule. It will stick to the start date and time for the one-time deployment.
See: https://learn.microsoft.com/en-us/azure/automation/update-management/overview
Please let me know if you have further questions**
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