Is there any more information regarding the event below?

993.999.M41 - A flood of distress signals and cries for help flood through the Imperium. Entire Astropathic choirs are overloaded and collapse. Anarchy and panic spread as the Imperium's communication systems fail. From Segmentum Pacificus there is only eerie silence...

What little information there is about Segmentum Pacificus basically ends with this event. So, was contact re-established?
And what was this event, was the cause for it ever stated?

Logically contact should be re-established, because of the Indomitus Crusade and how it states that primaris marines are to be given to all existing chapters.
Since there are space marine chapters within Segmentum Pacificus this would suggest that contact with the segmentum was re-established.

Thanks in advance.