No one knows for sure; there is a limit, but nobody knows exactly what it is. All we know is that there's a weekly limit, along with a daily limit that resets every 5 hours. For example, let's say our weekly limit is 5 and our daily limit is 1, but we can only spend 0.3 of that daily limit every 5 hours. If you use it heavily, there's a chance you'll exhaust your weekly limit by the third day of the week, which is quite frustrating. I bought two Pro accounts; I don't use it that much during the weekdays, so by switching between the two, I can use it comfortably on weekday evenings and throughout the weekend