Half Blood Prince: two sentences missing from UK edition

[Judy]

Oops, sorry. I had heard that it was the two previous sentences that 
were missing (and didn't have a UK book to check), and then missed your 
statement that it was the two middle sentences.

Anyway, I think my belief about this is still the same.  Probably, JKR 
wanted to change this paragraph, and only one version got the updates.
Now that I see which sentences were actually missing, I suspect she 
just thought the paragraph was too long.

-- Judy