According to Toshis
official ameba blog, to be released on September 30th is the first press of TOSHI DUET 1~永遠に旅すること~ (TOSHI DUET 01, ~Eien ni tabi suru koto~, which means 'eternally traveling') which will feature Toshi himself with two female vocalists.
Further details to be announced when they become available.
Thanks to PN for the translation.
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