Setting the "vaporware" aspects aside, I would say there's a good chance this machine will run some rebadged OS referred to as OS5. If for no other reason than the ownership of OS4 coming into question.
That means you should see OS5 in around, er.... 6 years time! :-D
That would be the simplest solution from a business standpoint. Abandon all backwards compatibility, abandon the old OS. Move forward with new hardware and a new platform.
.....& then it isn't an Amiga! ;-)
