Anyone else seeing an issue where Sierra machines don't show the clock, Wi-Fi and battery info on the Login Window? I've seen it on machines that we've upgraded to Sierra as well as a machine that we've clean installed. Both instances so far happen to be 11" MacBook Airs.
What I've found is that if we intentionally execute a failed login attempt, something in the login window reloads and then the menu bar info shows up correctly. Our machines are all bound to AD.
I've also reproduced the problem both while applying a login window payload as well as without any managed login window settings.