A possible sighting on Mr Collett in Darling Downs has now been ruled out.
Police have spoken to two girls on horseback and have confirmed the sighting of a man in Darling Downs on Sunday was not Ian Collett.
Crews are no longer searching the Darling Downs area for the 65-year-old.
The search will continue in the Bedfordale area with the Forward Command Post moving from Bedfordale to the Mundijong Police Station.
Inquiries are continuing into the whereabouts of Mr Collett and police ask anyone with information regarding his whereabouts to reach out on 131 444.
Although the last confirmed sighting of Mr Collett was around midnight in Armadale on Saturday 19 May 2018, police are not discounting that he could be in another area.
City of Kwinana proposes 4.5 per cent rate rise
Recreational boat fishers offered $50 rebate for fishing gear at participating tackle shops
Waikiki teen among the best CrossFit athletes in the world
Mandurah's Kerrie Overell crowned WA Volunteer of the Year
Wellard home destroyed by fire
Woman fined $7k after catching 134 undersize crabs in Coodanup
Mandurah mayor Amber Kearns 'disappointed' in councillor Peter Rogers' decision to resign
Speed limit dropped to 70km/h on stretch of Mandurah Road in Secret Harbour
WA Police officer tragically dies in hospital days after Hopeland crash