Contributor Ignacio Gully explains:
AmigaOS 3.1 was never supposed to have been released. It was Village Tronic GmbH, makers of the Picasso series of graphics cards, that released it for their customers as it contained a few fixes that were valuable for ReTargetable Graphics (RTG) card owners. Village Tronic was a registered developer of AmigaOS, as many other companies were, so they had early access to confidential ongoing development work, which included what we now know as OS 3.1.
Commodore sued them because of this, and ended the 3.1 distribution. But given their opportunistic nature, Commodore realized that it was a reasonable idea to release whatever sellable content they had for 3.1. So, it quickly became an official release, despite originally being an unintended one.
Before Commodore went bankrupt on April 29, 1994, the following updates to OS 3.1 were in development, but either never finished or released:
"Ultimately, the 68060's highest volume market will be as an embedded processor in equipment such as printers and communications equipment, Reinhart [Jim, Motorola's manager of 68000 marketing] said. Eventually, the chip will be targeted more toward that market, Motorola indicated, and will lose backward compatibility with its predecessors. "We won't be responsible for 68040 compatibility in future generations [of the chip]," Reinhart added."
All this development was what would have been version 42 of the AmigaOS, though with no specific number assigned to it. The work was far from complete and appears to be in an initial state; very much a work-in-progress development halted by bankruptcy.
Of course, later, by approximately 1996 some development work resumed under Escom/Viscorp And Amiga Technologies, but that is just another chapter of the Amiga story.