Alain Prost has added his scepticism to the new aerodynamic rules for 2019.
In the paddock, opinions are split as Liberty and the FIA move to make overtaking easier.
"It was a change in the regulations that cost us a lot of money before another major change of regulation for 2021, the details of which are not yet known," F1 legend and Renault advisor Prost told RTBF.
"Perhaps it would have been better to wait until 2021 and fundamentally change a lot more," he added.
Based on winter testing, some drivers have said the new front wings in particular have made following a rival car easier.
Prost said: "In testing you don't necessarily follow another car often, so we cannot say yet if it will be easier to follow and overtake, but there is a small tendency to say that is positive.
"I hope it will be positive, but I am not completely convinced that it will be day and night," he added. "We will not see the different in Melbourne anyway, because it is a circuit where it is always difficult to overtake."
