Hi. I'm trying to find information about what happened at Hogwarts while Harry, Ron, and Hermione were off on their adventure during Deathly Hallows. Can anybody help me out?

I had a question about something which I'd heard but never really bothered to check: did JKR really retcon Draco being slapped by Hermione into being punched by her (as depicted in the film version of PoA)? I've heard it reported that she did (via the text of HBP), but wanted to be 100% sure.