I don't know if this is already considered, but you may want to add a "Date Played" field on the survey. That way it can be compared to the dates on which errata is released.
For example, we'll be finishing up Part 2 this Sunday, before Monday's errata is released - so we'll be playing with the old dying rules, etc.
When I filled out my survey, it asked if I used the errata or not.