[Thanks to a reader for flagging this up via email]
Due to an error on my part, the redirect link in the red banner at the top of old baseline sites (for example) were pointing incorrectly to the atbref9. Now fixed!
URLs for much of the site has been stable over the years so simply changing the baseline number may get you the current papge. IOW, for an aTbRef6 page in the user change /atbref6/ to atbref10 to get that URL on the v10 baseline. Sadly large advances in action code in recent versions mean that the sections about action/export code, attributes and views (probably the more pages) did need restructuring in the source TBX meaning this trick fails.