The move, East claimed, could cost homeowners millions and result in increased socio and psychological issues for communities still recovering from the devastating 2010 and 2011 Canterbury earthquake sequence.
Community group Christchurch Coastal Residents' United (CCRU) backed calls for an independent inquiry, as did Darrell Latham, Linwood-Central-Heathcote community board member, who called the omission "red-zoning by stealth".
"Ultimately we are here today to right a serious wrong and to seek justice and accountability," East said.
Today, East has emailed Prime Minister Jacinda Ardern and Local Government Minister Nanaia Mahuta with his concerns.
However, he has not yet raised anything with the city council and Mayor Lianne Dalziel – a move East admitted was "unfortunate and regrettable".
Tim Sintes, deputy chair of the Coastal-Burwood community board, said the "unjust action" in leaving out the clause from district plan is "heartbreaking" for some residents.
Some people have already moved out because they were told they couldn't extend their homes or build again, Sintes said.
"It actually destroys an area, some of these rules," he said, while adding that it results in added mental stress for already vulnerable communities.
This afternoon, Christchurch City Council's acting chief executive Brendan Anstiss responded to say it was "hugely disappointing" that East and other elected members "have made these serious allegations without basis" and not raised the concerns formally with council.
Anstiss said it was "inappropriate" for an elected member to make accusations about alleged staff misconduct in a public session "without providing any supporting evidence".
"I have full confidence that staff have acted professionally in their role in giving effect to the Independent Hearings Panel decisions," he said.
Council staff provided evidence to the Independent Hearings Panel, which made the final planning provisions, Anstiss said.
"It was not their role to question the intention of the panel in their decision making," he said.
"Unfortunately Councillor East appears not to understand the decision-making process of the Independent Hearings Panel.
"It is now the council's role to give effect to the Independent Hearing Panel's decisions. I am confident we are applying these decisions correctly.
"If Councillor East wants to raise this issue formally with the Council, he knows the process to do this."