Today I made some edits (added questions) to a survey I distributed last week. However, the respondents that I've talked to since making the changes are still seeing the old version of the survey. What is going on?

I wonder if it is possible that the people emailing you had already clicked in to (i.e. started but not submitted) the survey? Once someone has started a survey they will continue to see the version of the survey that they originally saw.