Ask Apple. If Apple told me when I would know. They will slow down the phone without my knowledge. Heck it would be better if the phone unexpectedly did shut down. At least I would know there is a problem with the battery. In the solution Apple implemented the user may feel the phone in general is slow and upgrade to a newer phone without realising a $80 battery is the solution.And this power management will commence when?
[doublepost=1514005780][/doublepost]
Yes let's discuss it.
Apple heavily throttles the CPU based on battery.
Apple didn't tell anyone it does so.
Apple throttles the battery even when the battery passes all diagnostics and is above the threshold at which they recommend changing it.
Apple let people believe their phones were physically fine and thus any slowdowns would be iOS related as they have been the past decade.
People would have purchased new phones based on the poor performance as there would be no indication of any other way of addressing the poor performance.
They even fooled a pro user like me. A guy who installed custom ROMs on Android. Never in my wildest dreams would I link battery wear with performance.