When does voting take place once an initiative is qualified for ballot?

Federal Law on Popular Referendum (March 14, 2014)

Article 30. The Call of the popular referendum shall include:

I. Applicable legal grounds;

II. Date of the federal electoral day in which the popular referendum will take place;

III. Brief description of the matter on the national significance topic submitted to the referendum;

IV. The question that will be asked, and

V. Place and date of the release of the Call.