iOS 10.3 arrived at night and treachery, well, it actually arrived at the same time as always, only maybe we didn't expect it too much. In the same way, iOS 10.3, as an important update to the operating system that it has been, has brought some other changes, such as that of the iCloud section in the settings menu. The problem is that apparently According to an error that hundreds of users seem to have suffered, iOS 10.3 has reactivated certain iCloud services without notifying its users. That is why, as in many other occasions, we must take a look at our configurations after an update in case this type of thing happens.
The iCloud team itself has commented to a reader of MacRumors which they certainly suffer from this type of problem with the activation / deactivation of iCloud services automatically when updating to iOS 10.3
We have discovered a recent bug in iOS 10.3, the software update has had some negative impact on a limited number of iCloud users. This could have reactivated some iCloud services without requesting permission or notifying the user, especially services that were previously disabled by the user.
That is why we suggest that you take a tour of the iCloud settings to see what services you have activated, or otherwise contact AppleCare for any questions.
Since March 27, when iOS 10.3 arrived, there has been a major change in the iOS file system that seems to be the main reason that the iCloud services settings have changed. The iCloud products that have been affected are iCloud Drive, Photos, Mail, Contacts, Calendars, Reminders, Notes, Safari, News, Apple Keychain, Find my iPhone and the backup, so In view of the importance of these services, it is time to review the adjustments.