Created attachment 16702 [details]
Sample to reproduce bug
DateTimeOffset on iOS doesn't get the correct offset if you change the Time Zone while the app is running. It correctly updates only from a fresh start.
Attached is a sample that demonstrates this.
To reproduce on iOS:
1) Launch the app on an ios device (not simulator) and take note of the time zone offset.
2) Background the app and change the Time Zone under Date & Time in iOS Settings
3) Foreground the app and notice that the Offset information doesn't update to reflect. (The sample will auto reconstruct the view on resume, or you can tap the refresh button)
The offset information should update as it does on Android.
Android works as expected
Should be fixed in 2.3.4-pre1
I have checked this issue with Xamarin.Forms 2.3.4-pre1 and its working fine.
Hence closing this issue.