The French manufacturer, which joined the WEC for the final three races of 2022, has already undertaken two Le Mans 24 Hours simulations of more than 30 hours and has confirmed that there will be a third prior to the 1000-mile WEC opener at Sebring in mid-March.
Peugeot undertook its first endurance test with the 9X8 at Paul Ricard in the run-up to Christmas and its second at the Algarve circuit in the New Year.
The third is imminent at a time and venue that has yet to be disclosed, although it is understood to be Aragon.
Olivier Jansonnie, technical director on the 9X8 project at Peugeot Sport, told Autosport that the two tests so far had thrown up "some positives and some negatives".
"At this stage of the programme we have a mixed feeling, not black and white," he said.
"We had confirmations of some failures and we also brought in some new systems that were pretty good from the start."
Jansonnie stressed that there were no concerns as Peugeot gears up for its first assault on Le Mans with the 9X8 in June.
"Being 100% ready for Le Mans in December or January wouldn't have made sense," he said.
"It would have meant that we hadn't pushed the development enough, so we are not quite there yet."
He insisted that the first step was to be ready for the Sebring 1000 Miles on 17 March.
"Sebring is imminent, so we need to make the last step of the validations to define properly our package for there," he said.
The winter test programme followed three races in which Peugeot failed to get one of its two LMHs to the finish of a race without problems.
The issues encountered included one with the oil system that afflicted both cars at Fuji in September and then gearbox and fuel pump problems at the Bahrain finale in November.
Jansonnie confirmed that Peugeot had opted against testing at Sebring prior to the official pre-season prologue the weekend ahead of race week.
He explained that a focus on endurance testing in Europe was "the clever thing to do considering the logistics of getting a car to Sebring".
Peugeot is now subject to a limitation on testing after being able to run without restrictions last year.
The endurance tests, which included through-the-night running, were undertaken with a single development car.
The concept of the 9X8, which does not have a conventional rear wing, remains unchanged for the new season, but Jansonnie explained that differences will be visible between the 2022 and '23 versions.
Manufacturers are allowed five so-called 'evo jokers' or performance upgrades over the life-cycle of an LMH, but Jansonnie wouldn't reveal how many have been invoked for the uprated 9X8.
Updates made in the name of reliability are free.
