HHNRecordsPR (talk+ · contribs · deleted contribs · tag · block user · block log · CheckUser)
As for identity, it's the classic "I made that comment with the wrong account, so I better go change the signature strategy. As for abusive sockpuppeting, they both participated in Wikipedia:Articles for deletion/HHN Records, (see this deleted edit for HHNRecordsPR)and it's pretty obvious that HHNRecordsPR had a pretty strong motivation for keeping the article and disguising his identity during the argument.