I am currently attempting to increase character limits for some of my long answers questions within my survey. By simply bumping up character limit and trying to republish the survey I am given an error message telling me I will lose all my previous data. I can however add a new question which asks the same question but increase the character limit and publish the survey without issue. My question is, if I delete the old question from the survey will I lose the data? Will the field disappear from the old submitted surveys attribute field?
According to the Survey123 FAQ, see link below, "Edits that do not require changing the schema of the feature service can be made without issue." Additionally, the documentation for publishing a survey, also below, contains a table with changes that can and cannot be made without losing data.
In general, as with any data management workflow, it is a good idea to maintain a back-up copy of your data when making any changes.
Hope this helps!