I just called support on this. On the Business Info Tab, put yes for "Has an Ownership Change".
Then on the Partner/Membership Information tab click Done.
Select: No, there was not more than 1 date.
Then put in any date other than the first day of the year. It will then prompt you for the %s for both before and after that date. If you put in the first day of the year, it won't prompt you.
