A week after the release of watchOS 5.1 which brick several Apple Watch, watchOS 5.1.1 is now available for all users.
The update as you remember it was indeed withdrawn because of the problems mentioned above, which forced Apple to recall the Apple Watch affected by the bug that caused some devices to be non-functional.
The novelties of watchOS 5.1.1 are minor and are limited only to the support of group audio calls through FaceTime, to new watch faces and of course to bug fixes, with related performance improvements. No news yet about the ECG function, which will initially be available only in the US, which seems postponed to other future updates.
watchOS 5.1.1 is available for all Apple Watch except the first generation model and can be installed via the Watch app on iPhone. with Apple Watch on charge and at least 50% battery.