Greg Lynn's 4WD was painted a different colour when police attended his home months after he allegedly murdered Russell Hill and Carol Clay, a jury has been told.
Lynn, who was a Jetstar captain at the time, is accused of killing the couple on March 20, 2020, in Victoria's Wonnangatta Valley and then dumping their remains in bushland.
The 57-year-old has pleaded not guilty to two counts of murder and is on trial at the Supreme Court in Melbourne.
Detective Leading Senior Constable Abbey Justin on Wednesday said cell tower records showed Mr Hill's phone was near the Great Alpine Road at 10am on March 21, the day after the alleged murders.
Police accessed CCTV footage from the road and found only one vehicle had come from the Wonnangatta Valley in that period, she told the jury.
Sen Const Justin said the vehicle was a grey-blue Nissan Patrol registered to Lynn.
She first attended Lynn's Caroline Springs home on July 14, 2020, and saw his vehicle parked on a side street but it was painted a light-brown colour, the jury was told.
She admitted it might have been a "sand bank" colour when quizzed by Lynn's barrister Dermot Dann KC.
Lynn had told police he painted his car that colour after the Wonnangatta trip, Mr Dann said.
Sen Const Justin also gave evidence about Lynn's bank records, which showed he purchased fuel in Mansfield, west of Wonnangatta, on March 21.
It's alleged Mr Hill and Mrs Clay died on March 20 after an argument between Lynn and Mr Hill at Bucks Camp in the Wonnangatta Valley.
Mr Hill had threatened to send his drone footage of Lynn deer hunting near the camp to police, Mr Dann told the jury.
He claimed a scuffle broke out after Mr Hill took a gun from Lynn's vehicle and Mrs Clay was accidentally shot by Mr Hill.
The barrister said Mr Hill came at Lynn with a knife and was accidentally stabbed in the chest as Lynn defended himself.
However, prosecutors allege Lynn intentionally killed Mr Hill and Mrs Clay.
Lynn burned Mrs Clay and Mr Hill's campsite, put their bodies in his trailer and dumped them on the remote Union Spur Track, near Dargo.
The trial continues.