I have a WSUS server and configured my clients for an update check heartbeat of one hour.
[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate\AU] "DetectionFrequencyEnabled"=dword:00000001 "DetectionFrequency"=dword:00000001
I can see in the windows update log that this is functioning and my WSUS server also shows the windows reporting in at hourly intervals.
When I approve an update and its picked up and downloaded, Windows does not immediately install. This is as expected because I've set a daily scheduled install time of 12:00
[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate\AU] "ScheduledInstallDay"=dword:00000000 "ScheduledInstallTime"=dword:0000000C
My windows update screen shows the pending installs.
I also see that the update check heartbeat seems to stop working once the updates have been downloaded and are pending installation. Adding further updates for that PC in WUSUS doesnt trigger them to be downloaded and added to the pending install list. Even if those updates are marked with a WSUS Deadline in the past (which should trigger immediate installation after download) the presence of pending installs seems to block the update check heartbeat from happening.
I can't find any documentation on this so want to know whether this is an 'known issue' or 'known expected behaviour'