CNBC reported on speculation over the weekend that a physical crack may have developed in the FPSO which could add billions of dollars in upfront costs that could delay even further the project which has already suffered cost and time blow-outs.
A person "familiar with the project" told CNBC they had firsthand knowledge of an "unannounced crack" in the FPSO, which is sitting in a yard in Busan.
This crack, the source claimed, was driving up costs and delaying the FPSO's journey to Australia.
CNBC said three other sources said they had also been told there was a crack, but could not independently confirm the defect.
CNBC said Inpex's response when asked whether the rumoured crack was real was that it "cannot provide details concerning reasons for the delay".
Another person familiar with the matter said Inpex recently hired as many as 300 welders to fix the damage, and several sources said they believed the damage was the main reason for the delay out of the yard.
Yet an Inpex spokesperson told Energy News that the FPSO facility construction and commissioning was now complete, and that the company was progressing the final preparation activities and checks prior to sail-away.
"Ready for sail away for the FPSO will be achieved following completion of these final preparation and checks. Sail away will follow, pending weather conditions," the spokesperson said.
A spokesman also said any cost overruns could be up to a few percent of the previous estimate for the project of around $US37.4 billion ($A49.2 billion), despite Inpex announcing in September 2015 that the project would cost 10% more and take 6-9 months more.
Then in April this year Inpex amended the schedule to start up by the end of March 2018 rather than this September quarter.
Daewoo Shipbuilding & Marine Engineering also denied reports of technical problems in the FPSO, with a spokesman saying he was not aware of any crack, and that the FPSO would sail away this month, the exact timetable was not yet set.
One portfolio manager who reviewed Inpex's recent spending projections said that "with the 2018 capital expenditure guidance increasing by around 50% over the last six months, it may suggest Inpex has lost control over costs".
Wood Mackenzie called Ichthys a "game changer" for the Japanese company, writing in a recent note that "once up and running, it will bring Inpex into the elite LNG club of global LNG operators, dominated by the major international oil companies".