My CC account wants to update both versions!
They are two different versions of InDesign, just as CS6 is different than CS5.
This blog post by Terry White may explain it better:
Why do I have 2 copies of my CC Apps?
And the new update that is being pushed at you is really the DPS Tools, not ID program updates.
DPS has to be adapted to each version, so you'll see updates for each version of InDesign you have installed.
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