Brian Jones remembers it like yesterday.

Christmas Eve, 2018. A crack. An evacuation.

Sirens, fire engines. Police.

And for some, fear a building was about to collapse.

But there is another reason it sticks in his memory; his dog Rambo does not like alarms.

"The noise is too much for his little ears," he said.

Mr Jones owns an apartment on level 29 of Sydney's Opal Tower — now arguably Australia's most infamous residential building.

On Tuesday, Christmas Eve, when most of Australia will be wrapping presents and recalling past Christmases, Opal Tower residents will be remembering something else: the day they were evacuated from their homes.

Many owners spent months in temporary accommodation, an ordeal described as a "nightmare" and a "disaster", as they waited for repairs to be finished.

Superficial repairs are expected to continue at Opal Tower until April. ( ABC News: Brendan Esposito )

Finally home but promises yet to be delivered

A year on and, after spending $31 million, the builder Icon has confirmed all 392 apartments in the Olympic Park building are now re-occupied.

But what Icon describes as "superficial" repairs are ongoing and they will continue until April.

And conflicts remain.

"The lives of everyone in this tower were turned upside down," Opal Tower owner and body corporate chair Shady Eskander said.

Mr Eskander, a pharmacist who has become the unofficial spokesperson for the residents, said for the most part, Icon's approach had been admirable.

Shady Eskander, Opal Tower apartment owner and body corporate chair, says he wants Icon to keep its promises. ( ABC News: Brendan Esposito )

But he said there were still issues to be resolved, such as previously promised 10-week rental compensation.

"Our backs are being scraped," he said.

"We have worked hard, we have gone to the banks to get a mortgage, we have come and given our hard-earned money to developers, to the State Government with stamp duty.

"We need to learn what happened here at Opal Tower.

"And we need to ensure those promises are kept and that we are able to ensure no owner here goes out of pocket for an issue that was no fault of their own."

Opal probably 'safest in the world' now

A class action suit launched by residents in July is also complicating matters.

It has turned into a blame game, with Icon blaming the engineer, WSP, which in turn has launched a counter-claim against the company that fabricated the precast wall panels.

Legal experts predict the battle will play out well into 2021.

Visiting the site yesterday, Icon chief executive Nicholas Brown said he could not comment on the class action suit or the rental compensation claim as it was part of the class action.

He said the company had been there since "day one" and was committed to getting the best result for owners and residents.

"There are other incidents like this where the builder has vanished," he said.

"We didn't. Hopefully people will look back on how we acted."

Icon chief Nicholas Brown said the company was committed to getting the best results for owners and residents. ( ABC News: Brendan Esposito )

Mr Brown said the company was doing cosmetic repairs such as painting and landscaping, which it expected to finish by April 2020.

"Our structural work is complete, and we've started dropping the scaffolding now," he said.

Back on level 29, Mr Jones said he was trying to be optimistic about the value of his apartment, which he bought for $980,000, and the building which he said was probably now "the safest in the world".

"No-one would probably want to buy here at the moment," he said.

"But real estate is a long-term game.

"And I think over time people will regain confidence in what this building has undergone.

"It'll be a game of patience."