I was able to use the Cold War Intelligence and Weapons of Mass Destruction collections via the Wikimedia subscription prior to the expiration. I used them extensively prior to the moment they suddenly got cut off, and the access has never been restored.

Very curious if there are any updates on this — another month has passed by, access to the older resources is still impeded. This marks something like the 5 month point (I first noticed the outage around April, if I recall, after getting good use out of it in March).

As of now there seem to be some books available that are subscription-only, such as this one (as one random example) or this one (to give another). I am having trouble getting their (terrible) search engine to give me a real sense of what is and isn't available but it seems like some content is available under books.

All Brill primary sources still come up as "locked" for me. Many of these used to be "unlocked." Similarly, if you go to the main publications list, and click "Subscribed content," it says no content is available. The only content listed as accessible is inherently-open (non-paywalled) content ("Free content" or "Open Access"). Which is the state is has been in now for several months.