Airbus is grappling with a newly detected industrial quality problem involving fuselage panels on several dozen A320-family jets, slowing deliveries at a critical point in the year, Reuters reported.

The suspected manufacturing flaw, disclosed to Reuters by people familiar with the matter, has not so far been linked to aircraft already in service.

The issue has begun to ripple through Airbus’s delivery schedule, the sources told Reuters, requesting anonymity.

Airbus declined to comment when approached by Reuters.

The cause of the problem has yet to be pinpointed. Its emergence comes as the European planemaker pushes to close the year with an ambitious delivery tally, while dealing with the fallout from a weekend recall of aircraft triggered by a software glitch.

A person with knowledge of the situation told Reuters that some deliveries had already been affected, though the scale and expected duration of the disruption remained unclear.

Industry figures shared with Reuters suggest Airbus handed over 72 jets in November, taking total deliveries to 657 for the year to date, fewer than many analysts had projected.

The manufacturer has been aiming for “around 820” deliveries in 2024, a target that would require an unprecedented December push of more than 160 aircraft.

The company’s highest-ever monthly tally stands at 138, set in December 2019.

Analysts are split over whether the world’s biggest commercial aircraft producer can still reach its full-year goals, a metric that influences revenue and cash flow because airlines settle most of an aircraft’s price upon delivery.

Jefferies analyst Chloé Lemarié, who monitors monthly handovers and had forecast 71 deliveries for November, called the month’s figures underwhelming.

She said in a client note, written before Reuters reported the quality issue, that rising production rates still kept the year-end target achievable.

Independent aviation expert Rob Morris told Reuters that Airbus could still land close to 800 deliveries.

That number, some analysts argue, might be enough for the company to claim it has met its guidance depending on how the forecast language is interpreted. But Morris warned the final tally could end up “marginally lower.”