But, according to sources close to the case, the hearing was postponed and is now set to take place during Armstrong's trial, which has been delayed until July 31.
READ MORE: AJ Armstrong's 3rd murder trial delayed until July 31 due to 'ongoing issue,' judge says
What's likely blood evidence has been found on Armstrong's gray T-shirt, sources say.
He was allegedly wearing that shirt the morning he was arrested and charged with killing his parents, Dawn and Antonio Sr., in their southwest Houston home in July 2016. Armstrong was 16 years old at the time.
Within the last few weeks, the T-shirt was retested at a crime lab after what appear to be flakes of blood were discovered under an adhesive HPD visitor's badge that had been stuck to his shirt, sources say.
The badge was believed to be put on Armstrong by someone else because he was handcuffed when he arrived at police headquarters for his interview with officers.
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It's unclear why, after nearly seven years, this new potential evidence was just discovered.
Both prosecutors and defense attorneys are not commenting on the case at this time. Judge Kelli Johnson has issued a gag order, preventing them from discussing theories and opinions on evidence.
At this point, there has been no decision on whether or not this new discovery will be allowed in trial. Judge Johnson will make a decision when the hearing happens during the trial, which is set to start on July 31.
See more of ABC13's seven-year coverage on A.J. Armstrong's murder trial.
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