This was in a dif thread but thought it was worth posting in a separate one, as the title of the other one wouldn't indicate this.

"I was just on the phone with a UAL rep to see if they would do the HH transfer. She said they received notice that as of this AM they are not to do the HH OR the DINERS CLUB transfers."

I'm guessing HH decided to block the Diners route so that people couldn't do UA-DC-HH. Of course the downside is for people who have legit Diners points that might not be members of UA that want to transfer their Diners into HH, and of course the other obvious downside for those that were willing to take the hit on UA miles into HH via DC just to get rid of UA miles.