Level 5 has some unannounced games in the pipeline. Maybe one of them is called Time Machine Story. Or Time Machine People. Level 5 filed trademarks in Japan for Time Machine Story and Time Machine People (written in katakana and kanji) late last year.
Any of these could be a subtitle for the localized third Professor Layton game, which involves time travel. However, I think that scenario is unlikely since Level 5 registered their names in Japanese, not English. Also, Level 5 filed three trademarks, a sign that Time Machine Story is an important intellectual property, whatever it is.
Special thanks to liamscanlan for reminding me to check on Level 5 in the Japanese trademark database.