Details about the early vocalist change are unclear. There are two versions of the band's first demotape, ESCAPE FOR PRESSURE, and it seems that the first version credits KA-TSU while the second version credits MANABU (although even this is unconfirmed).

The release dates of the two versions are completely unclear; some sources state that the release date was November 1993, others state February 1994, and M GAZETTE VOL.4 states March 1994. No source even mentions that there were two versions.

Assuming that the vocal credit did change between the two versions, and assuming that multiple sources have correct dates, we might guess that the vocals changed from KA-TSU to MANABU sometime between November 1993 and March 1994.

However, M GAZETTE VOL.4 also mentions the real name of then-vocalist MANABU: Katsuura Manabu (勝浦学). Given that Katsuura is very similar to KA-TSU, and the fact that it would be fairly odd for an indie vkei band at this time to re-release a demotape with only the vocal tracks changed, it's possible that he simply changed his name.