gh aw add-wizard on a scheduled workflow should offer a choice of hourly/3-hourly, daily, weekly, monthly triggers
It should default to whatever is in the workflow
The workflow frontmatter should be adjusted carefully and reliably to reflect the choice. Unless the choice was the default in which case no change made.
Sometimes the frontmatter will have a custom schedule not corresponding to the above, in which case "Custom" should be listed as a choice.