InfoPath Dev

We have an Infopath form that has a Notes section that is a repeating text box data type. We need this Notes section to contain a log of the previous entries along with the newest entry when an item is edited. Is it possible to convert this field or is it a case of adding a new field?

Is your form already in use? If you change the field, you'll lose data previously entered, and in the case of a browser form, old XML may not open with the updated template. You can add a new field and then a form load rule that uses a double eval to concatenate the existing notes and put them in the new field.... but I'd be concerned about users deleting the existing data when they go to add their latest note.