Speculation:
One thing I could see occurring is Mitsubishi wanting to receive carbonate from GXY and setting up a JV with GXY to build a converter here in Australia. Potentially value unlocking that part of the supply chain for GXY and Mitsubishi as well as allowing Mitsubishi to have a JV partner with experience in setting up and operating a converter in Jiangsu. Mutually beneficial imo
N.B Strictly IMO and a speculation, nothing more.
Edit: Apologies @Thesi this is very similar to your speculation, I managed to skip over your posts whilst scrolling down to write my post! Good to see we're on a similar wavelength!