Boeing said Sunday some 50 undelivered 737 MAX jets need more work after its supplier, Spirit AeroSystems, identified misdrilled holes on some fuselages, Reuters first reported.

Why it matters: Boeing's reputation was hit following the mid-flight Alaska Airlines incident that led to the temporary grounding of 737 Max 9s in U.S. territory, and this latest issue could delay some near-term 737 deliveries.

• Boeing's commercial chief Stan Deal announced the potential delay on Sunday in a memo to staff that noted "this is the only course of action given our commitment to deliver perfect airplanes every time."

Driving the news: "This past Thursday, a supplier notified us of a non-conformance in some 737 fuselages. I want to thank an employee at the supplier who flagged to his manager that two holes may not have been drilled exactly to our requirements," Deal said in the memo, in reference to Spirit, Boeing's only 737 fuselage supplier.

• Deal emphasized that "this potential condition is not an immediate flight safety issue and all 737s can continue operating safely."
• He added: "While this delay in shipment will affect our production schedule, it will improve overall quality and stability."

State of play: Boeing said in an emailed statement late Sunday that the aircraft maker was finalizing rework instructions for affected airplanes and it expected to have an estimate of rework time in the next several days.

• The company stressed that this did not represent a pause in deliveries and that any 737 with an unaffected fuselage can be delivered, while further checks will be carried out on undelivered planes before they're delivered.
• A Spirit spokesperson told media Sunday the supplier is keeping close communication with Boeing on the matter.

Flashback: Misdrilled holes on some Spirit-supplied fuselages last year caused some delays in production for some MAX planes, the Wall Street Journal notes.

Go deeper: Boeing 737 MAX 9 planes have returned to the skies