The Federal Aviation Administration (FAA) expects to receive Boeing 737 MAX final software fix in the coming “weeks”, potentially revealing that planes might remain grounded for even longer than previously expected.

While Boeing was expected to submit the software update to FAA  around April 1, 2019, the update should not be ready for “weeks”, according to the FAA. The authority also explains that “time is needed for additional work by Boeing as the result of an ongoing review of the 737 MAX Flight Control System to ensure that Boeing has identified and appropriately addressed all pertinent issues”.

Boeing revealed the update of its software on March 27, 2019, describing the different “layers of protection” that it would add to it. Back then, the manufacturer stated that “we continue to work with the FAA and other regulatory agencies on the certification of the software update”.

The American manufacturer will also need to wait for the approval of the EASA and Transport Canada. The two authorities previously announced that they would conduct their own review of the update, independently from the FAA.

The 737 MAX software, in particular the Maneuvering Characteristics Augmentation System (MCAS), became the reason for world-wide groundings of the plane. Similarities between Ethiopian Airlines and Lion Air crashes have prompted speculation that MCAS malfunction occurred in both cases. Now, the Ethiopian Airlines crash report is expected to be published by mid-April 2019, providing more clarity on the topic.

Some sources already reported that the MCAS was involved in the crash of the Ethiopian Airlines flight ET 302, on March 10, 2019, thus confirming similarities with the previous accident of Lion Air flight JT610 on October 29, 2018.