McLaren staff worked throughout the Christmas break in order to keep its Honda-powered 2016 car on schedule.
Sauber, a smaller Swiss outfit, has admitted that it will not take a new car to the opening Barcelona test next month.
A team spokesman said the late change to the 2016 race calendar - with the Melbourne season opener brought forward by two weeks - affected Sauber’s plans.
"To accelerate the production would have cost us resources," said the Sauber official, "and it’s no secret that we are not a top team like that.
"We also didn’t want to rush things. So we are sticking with the first plan."
For the beleaguered grandee McLaren-Honda, however, it is a different story, as the Anglo-Japanese collaboration is desperate to improve after a woeful performance in 2015.
But Simon Roberts, operations director, admitted the fast-forwarded Australia race date was a problem for the original McLaren schedule.
"Our entire build programme wasn’t lined up for that!" he smiled. "So we knew we had a problem to solve.
"The build schedule is on a critical path — it (the car) needs to pass all the FIA safety tests and be ready for the first test, which was also brought forward."
Roberts revealed that, even though Christmas was looming, McLaren had to look into speeding up the process.
"In simple terms, we put about eight shifts of work back into the programme over a five day period — a fantastic effort," he said.
"In total, there were about 110 people involved and we looked after our Christmas workers with a competitive package. It was a bit weird, not having all the time off, but there was a good spirit in the place. Everyone knew why they were doing it, and it really cleared the decks," said Roberts.
"Most pleasingly, it meant that, once we came back in the New Year, we were back on schedule — and it felt like the programme had always been phased that way. It was an incredible effort."