I have surveys with a list of user names as a choice list. For standardization I am updating the surveys to proper names rather than network user names. No issues updating the list, republishing and having the new values appear in the survey.
However, I want to go back and update all the existing records to the new standard to allow for PowerBI to summarize by user. The only way I can see to edit the records is to use the Survey123 Web app and edit each record individually. The proper choice list appears when I use this method:

If I try to update using ArcGIS Pro, I'm stuck with the old list format, last name first name:

Same with trying to edit the hosted feature service directly:

The question then is, where is this choice list stored for existing records? Is the only way to update to use the Survey123 Web app? Looking at the REST endpoint, I see the old format for the coded values so it's as if they are embedded in the service.
Thanks for any tips!