iOS 16.6 has been in developer beta form since May. The upcoming iPhone software update will probably be released this month.
The summer time release isn’t expected to include any new user-facing features. Those are all packed into iOS 17 which is due out in September. Instead, the release will likely be one of the last updates to iOS 16 before shifting into strictly security-focused updates.
This release does not include any maj0r improvements or changes in the updated OS, despite iOS 16.6 having been released since may. That said:
The update is for iOS 16.5.1 and uses Apple’s Rapid Security Response system. This system allows security updates that do not affect the device firmware to optionally be installed automatically.
iOS 16.5.1 (a) and iPadOS 16.5.1 (a) Released July 10, 2023
Available for: iOS 16.5.1 and iPadOS 16.5.1
Impact: Processing web content may lead to arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited.
Description: The issue was addressed with improved checks.