The Wall Street Journal says Boeing may deliver the 737 MAX to customers much sooner than previously intended and has plans to give its new tech single aisle family a better wing, higher undercarriage and bigger engine further down the track.
These are significant developments in the contest between the already-in-service Airbus A320 NEO line and the similarly revised Boeing 737 MAX series.
Since the initial 737 MAX 8 flew last Friday its test program has been more like that of an in service aircraft, with at least three flights taking place since then.
The WSJ report says Boeing is aiming for first deliveries of the jet as soon as next March instead of much later in 2017.
However it also reports Boeing as talking to potential customers about what sound like very substantial design improvements for the MAX family, including a new wing, a higher ground clearance undercarriage, which would facilitate the reported offering of more powerful engines, and other changes.
These changes could overcome what are seen by some airlines and analysts as serious shortfalls in the performance or potential of the MAX line versus the NEO family from Airbus that are particularly noticeable at the higher capacity end of the Boeing and Airbus offers.
The Airbus 321 NEO has in terms of sales so far left the corresponding 737 MAX 9 variant floundering in its wake. The A321 NEO has invaded the natural territory Boeing had carved out for itself with its no longer in production 757 line, leading to the US planemaker floating various plans for an all new Middle of the Market or MoM jet, and an even higher capacity all new jet pitched at replacing 757s being used for notably longer haul routes, as well as the capacity of obsolete Airbus A300s and A310s.
The changes mentioned in the WSJ report would take some time to implement and certify, and result in jets markedly different to the MAX series as currently offered.
They might also cause a response by Airbus, most likely one it has been sitting on for some time in anticipation of Boeing moving to claw back what it has lost to the NEOs so far.
But not everything has gone to plan at Airbus either. The initial deliveries of the A320 NEO were held up by issues with the Pratt & Whitney geared turbo fan engine.
Plane spotters in recent days have seen the first A321 NEO emerge from its final assembly line carrying the alternative new technology LEAP engines on its wing, similar to the engine chosen for the MAX family, rather than the recently troubled P & W design.
The contest between the two engine designs is running in parallel to the Airbus v Boeing battle over the single aisle jet market, and like everything in the airliner game, nothing ever runs as smoothly as intended.