I believe this instrumental was only released when Aviators had the Constellations remix contest back when he was working on From All Sides. After that, I think Avi removed the link for the remix stems (which had the MIDI, instrumental, & vocals)

How did I find this? Let's just say: Someone left a download link somewhere..

Download: https://www.dropbox.com/s/7hxcbapx2ztd5hu/Constellations%20%28Instrumental%29.mp3?dl=0

Remix Stems (For remixing, of course!): https://www.dropbox.com/s/5emr3e7wnm0fgkf/Constellations%20Remix%20Stems.zip?dl=0
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