Quite a number of the most apparently useful of the KB articles from the old Knowledgebase have been ported to theHub, and may be readily found here by means of a search for their Article ID. There are currently 602 KB articles, release notes, and manuals - plus 16 videos - available here, mostly in the FAQ section. We are continually adding more, on a regular basis.
Moving forward, if and when you are made aware that any previously known KB article would be useful but is not presently on theHub, then feel free to request that it be ported to theHub - either as part of an otherwise open GTAC Support case or by request submission to this forum. When it has been ported - and this typically is a rapid process - you will be notified in order to close the loop.
What is the document ID in question? It may already be available.