"They've even called for the sacking of the Opera House manager who told them where to get off. Let's remind Alan that the Opera House truly does belong to everyone, by supporting Louise Herron's staunch defence of one of our city and country's few instantly recognisable heritage landmarks".
"It will be kept secure until it is released to the public on the Opera House tonight".
Many were also were angry over Alan Jones involvement in the incident.
Almost 3000 people are also expected to attend a protest at that time to disrupt the Everest projection with torches and mobile phone lights.
The controversial Opera House projection is due to take place at 8pm on Tuesday, when the barrier draw for The Everest will be projected on the Opera House sails.
"I hear what people have said about what they want to see the Opera House used for and what they don't want to see it used for". NSW Premier Gladys Berejiklian later overruled Herron and gave Racing NSW most of what was being asked. "These are issues that we take on board".
The protesters say they will disrupt the display with torches and mobile phone light, according to Fairfax.
The stunt was performed in the early hours of this morning and is in response to Jones' support for the iconic Sydney building to be used to promote this Saturday's Everest horse race at Randwick Racecourse.
It falls in the middle of Melbourne's marquee Spring Racing Carnival, a strategic move by Racing NSW who have ambitions to drag money and attention from Victoria.
Stewards held the barrier draw this morning behind closed doors, with betting on the event suspended until the results are revealed.
The top-rated broadcaster publicly berated and called for the sacking of Opera House chief executive Louise Herron on Friday after she ruled out allowing words or branding highlighting The Everest race to be projected onto the building.
The premier added she wanted to make it clear the move to go ahead was the government's decision after being accused of "caving in" to Jones' demands.