Set field value on page load but allow user to overwrite

I have an application that tracks educational courses and for each course, there can be multiple versions.  When my users create a new version, they want some of the fields on the form to default to values from the last published version (LPV).  I found a way to do this using a dynamic form rule that states: when the Course ID is not blank (ie - it's a new Version of an existing Course and not a new Course), change "Source File Type" to the value in "LPV Source File Type".  This works great for initially setting the value, however, my users need the ability to update the value.  In this particular example, "Source File Type" is a drop-down and the form allows me to change the value, but then the dynamic form rule kicks back in and sets the selected value back to "LPV Source File Type".  Is there a trick I can use that allows a value to be set on page load, but then allows it to be changed by the user?

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Dawn Quitschau
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