Hi James. Thank you for your SUPER fast response.
Partially correct - I am not seeing the update in the Survey123 field app (I am not sure what you mean by web context). I open survey123, go to the 'download surveys' page and see that the 'updated' date matches my last publish time. I then click the 'refresh cloud'. I see the downloading messages, then open the Survey. The old choice data are still present.
What i just did, however, was to use Survey123 app to delete the survey from my local machine, then re-download the survey. In that workflow, the new choice data are present. So it seems that the 'refresh' function isn't really updating the existing data. You need to remove the previous data first and then get the new survey.