Battery health issue

As I said above a 1 - 2% reduction in Battery Health per month is common. If you've owned your phone 8 months, an 11% reduction is within normal range.

You cannot stop Battery Health Decline. When battery health dips below 80%, it will be time to pay Apple to replace the battery in your phone.

Until then, you need to stop worrying about something you can't stop.

A few things you should do:

1. Never let the battery fully discharge
2. Don't let the battery go below 20%
3. Do plug your phone in to charge when you go to bed and leave it plugged in all night, every night
4. Read this link --> Batteries - Maximizing Performance - Apple
5. Stop worrying and enjoy your phone

No it hasn't. It's not cumulative from before the Battery Health was adjusted to after the adjustment. It just adjusted to be more accurate. So the health once it was adjusted was more reflective of the true health of the battery at that time.

I honestly wish Apple had NEVER added this reading to iPhone. People keep obsessing needlessly over it. Battery Health is going to decline. You can't stop it. Every phone, whether iPhone or not did the same thing. You just never had a setting to watch it in real-time.

Battery Health is inexact and with every full charge of your battery, Battery Health will decline, little by little. Its what batteries do.

ALL BATTERIES. A 1 - 2% decline per month is common. How many months have you owned your phone?