As an update, received email from Apple earlier this week to send in the phone for battery replacement anytime within the next 7 days.
Went to Apple Store at 1030 this morning. diagnostics showed cycles at 350. battery still ok but decided to change. Got my phone back at 1230. No cost cos covered under Apple Care. Can really feel the difference in performance on my Iphone 7+
Excellent service from the staff at Apple Store!!
So with AppleCare, battery replacement is foc?