Manufacturers and teams are busily assessing the impact of the newly-clarified engine 'freeze' situation, mere weeks before the season opener.
Pushed by Ferrari and Renault, the governing FIA has agreed to allow 2014 engine suppliers including reigning champions Mercedes to use their 32 development 'tokens' beyond the original start-of-season deadline.
And after a period of wrangling, newcomer Honda has also been let into the 'unfreeze', with McLaren's partner allowed to develop its turbo V6 on the basis of the average amount of tokens left over by its rivals at the Melbourne start.
But it means that, in effect, Honda is allowed to develop its engine less than its rivals in 2015, even though the Japanese marque does enter the season having been totally free to develop throughout 2014 and the winter period.
Honda is in
"Honda received the official news Saturday evening," a Honda spokesperson is quoted by Britain's Sky, "and we understand more or less the clarification from FIA, but we cannot comment on our situation just yet."
Also still assessing the unfreeze is Red Bull, who as Renault's works team struggled to compete with Mercedes' might throughout 2014.
"At the moment," said Red Bull, "the benefit or otherwise of the (unfreeze) remains to be seen.
"But the extra time will undoubtedly allow power unit suppliers to attempt to draw closer to a pacesetting outfit (Mercedes), though they too will obviously benefit from an open-ended homologation timeframe," the team added.
Mercedes to get more powerful?
A Mercedes spokesperson, meanwhile, said the German giant is "relaxed", even though boss Toto Wolff on Monday acknowledged the team is being chased hard by its rivals.
"We know that we went into the winter with a target on our backs for the other teams," he said, "and we are certain that our rivals will be competitive from the opening race in Melbourne.
"So we have to focus on every detail if we want to build any advantage this year and that is what we have done," added Wolff.
Mercedes customer Williams is also confident, according to Italy's sports daily La Gazzetta dello Sport.
A report quoted technical boss Pat Symonds as predicting that being allowed to develop into the 2015 season could actually "consolidate the dominance" enjoyed by Mercedes last year.