... I don't believe it is technically possible to have the choices for a multi select field be dynamic based on a formula.
The only other thing I could think of would be to have 14 checkboxes beside 14 calculated date fields would dynamically show the most recent 14 dates, turn them into some combined formula text field, and then have a form will save that calculated formula value into a scalar field.
It's an aside, it is actually not too difficult to create a pipeline which would run every night and rename fields so that the field names would correspond to the most recent 14 days. Then instead of having 14 checkboxes and 14 informational date fields to indicate which checkboxes is which, the checkbox themselves could be correctly named.
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Mark Shnier (YQC)
mark.shnier@gmail.com
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