Wrotevote will activate as soon as there are enough responses. Enthusiastic students might dive straight in.
Students can play as many rounds as they like, until they run out of pairs to review.
You might want to support this enthusiasm because it can make the activity appealing to other students and encourage them to complete the lesson, or you might want to tell class members when you want them to start playing.
For example you might want to let them play whenever they feel like, or play at specified times; play by themselves, or play as a group.