After Fawcett's conviction, police stressed that Ms Manning's death remained an open investigation.
However, Detective Senior Sergeant Brian Archer yesterday said inquiries have been hampered by Fawcett's appeal.
"We're in a bit of a legal limbo," he said.
"We're waiting for this process to come to a conclusion to know where we stand."
Fawcett's counsel and Crown lawyers are still preparing their cases.
NZME News Service understands that any appeal hearing won't be heard until at least February next year.
In the meantime, Mr Archer admits police are no closer to knowing just who the crucial "Male B" is.
Their best chance of catching the mysterious character was if he slipped up.
Whenever anyone is arrested and has a DNA sample taken from them, it is run through a national police DNA database.
"We're hoping that someone is arrested on an unrelated matter and we catch them that way," Mr Archer said.
"It is one of those cases where there were clearly other people involved and we would like to make those people accountable as well. It's not gone away and it is something that the family want as well."
Ms Manning's brother Rob yesterday said he hoped that the difficult appeal process, which "brings it all back and fires up the emotions again", would have been completed by now.
He is still seeking justice for his sister's bloody murder.
"What gets me most is that there are other people out there running around with blood on their hands," Mr Manning said.