You can make changes to your script while interviewing is in progress.

New interviews always use the latest version of the script; interviews that are in progress continue using the older version. If an interview has timed out or has been stopped on the older version of the script and is restarted on the newer version, the interviewing program silently replays the interview until it reaches the point at which the interview timed out or was stopped. However, if you have added extra validation statements that make some of the original answers invalid, the interviewing program stops where the error occurs and wait for the respondent to correct the answer.