Lexus Australia had planned to launch the all-new LS460 in November, without a raft of luxury features available in other markets.
While the Australian cars would have had the unique eight-speed automatic gearbox, they would have come without active damping, air suspension and the trick variable gear ratio steering standard in most world markets.
It is now likely that a full-fruit LS460 will launch alongside the LS600hL - the long-wheelbase V12 hybrid limousine around March.
"It is imperative that LS460 and LS600hL both launch with significant feature advantages," Lexus Australia divisional manager Scott Grant says.
"The LS460 introduced in Australia must be equal in specification to that in all world markets."
If that is the case then the radar-based active cruise control and lane shift warning systems - both of which had been trimmed from the LS460 for the original Australian models - should be back in the mix.
Company insiders say the decision to delay the arrival of the car until a fully-specified model is available came "right from the top" of Lexus Australia.