findmypast.com and NBI

I see that findmypast.com now has the NBI from FFHS. The site states:

"Whilst not all of the 13 million records from the second edition are
available here, millions of them are, alongside many thousands which do not
appear on the CD."

In respect of the "thousands which do not appear on the CD" can anybody
advise where these have come from? Are they further work by the same
FFHSs, post publication of the NBI2 CD i.e further parishes/later dates
etc. or are they from counties/parishes that were not covered at all on the
CD.

I assume that the aim is to put the whole 13 million from NBI2 on the site
eventually and stop selling the CD. In the meantime I'll just have to to do
two searches, first on the CD and then online. I notice that the online
Search does not allow you to drill down to <Place> only <County> which I
think is a bit cheeky!
--
Terry
.