Oh, now I understand what you are asking. You are right that updates can be right away or up to 30 minutes. I read one developer saying that with OS3 they can update up to 50 times per day but they need to choose when and how often.
I was trying to get sports scores to update like you were asking and it never did. I could force updates instabtlt by having notifications for every score, etc. that worked but it required notifications.
When I opened carrot for example, it would have the current or would update within a second or two.