Two of our users have reported the exact same behavior.
When looking at their logs, I can clearly see their schedules being created with a 300 minute event threshold, but the eventDidReachThreshold callback happened after 150 minutes. Note that when this premature callback happens, it does not send a eventWillReachThreshold at all, even though the warningTime is set. This is with app usage that does not include Safari, so it's not just a browser time tracking issue.
I'll try to isolate a repro, but this is really concerning.
steebee
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