Have BT SINs been "account-walled"?

I might have missed a mention of this on the forums, but it doesn't seem possible to access them as a member of the public any more.

What are BT's sins?

(Flippant answers accepted on condition of definition...)

In reply to a post by Woolwich:

What are BT's sins?

(Flippant answers accepted on condition of definition...)

For their SINs it is Suppliers Information Notes

If the answer given below (what's a SIN?) is correct and you are looking for Supplier Information Notes, I can see them here.

The link that Woolwich gives works for me too (tho' Chrome's "Resolving host" is rather slow).

The SINet pages have been undergoing reorganisation for a few months, the Openreach-specific ones are now hosted on the Openreach website. The BT-specific ones, plus links to the Openreach-specific ones, are accessible from the new main page https://www.bt.com/about/sinet

Thanks to Woolwich for the initial link to the Openreach ones and yourself for the complete list and explanation.

That's a big relief. I was worried that they had been moved to to the areas where you need a CP/ISP account or login like so much other stuff such as the BT Wholesale FTTC Handbook have been for years.