Store page: "developed on a personal computer"

[Topo]

The store page says that Heiankyo Alien was first developed on a personal computer. But on which one? I find contradicting information on the internet: Apple II or PC-8001? First Apple II, then recoding for PC-8001?

[mickyalbert1971]

Developed for Apple II at first but it was not released. TK-80BS version was published first. 2nd was PC-8001.