After Effects is set up to read the folder names as OCIO config titles and will pick the first in order as default when either opening a new project, or switching from Adobe managed.
I think this is problematic because ACES 1.2 is a legacy config that nobody should use ideally. (removing it in next release would be even better imo, ACES 2.0 will release soon and there'll be too many pre-installed configs).
The ideal would be that the Studio variant with latest ACES version and the latest OCIO config version is picked by default.
Furthermore I think AE should remember the chosen settings (even if it's custom) when exiting the software or switching back and forth between OCIO and Adobe managed.
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