The "professional" interview is specific to the French legislation. It is a mandatory event which takes place every two years (the period between two so-called deadlines spans two years). It must be distinguished from the 'performance' interview which takes place every year.
For all other types of interviews, these fields are entitled From evaluated period and To evaluated period. The period applies to the evaluated period.
For example:
Let us consider an interview campaign for the year 2011.
The interview forms are generated on February 1st 2012.
Consequently, interview forms are generated for those employees with: