The rule as written looks to me like it should do what you expect, not what you're observing. [EDIT: I missed the different trigger, so that's probably it unless you're confident that they are the same...] Are you sure there isn't another rule that might still be acting on these events?
That being said, here is another pattern you could model your rule after. I usually refer people to this when they ask about repetitions in rules while certain conditions are met:
In related news, if @bravenel ever gets bored, adding repeated notifications like this (e.g., "keep notifying every X minutes" until the condition that created the event the original notification was sent for is no longer true) seems like it might be a useful feature request for the Notifications app. I see a lot of people struggling to write rules like the above, and the app could almost meet their needs except for this.