Applying `xcalib -a -c` restores the default color temperature until the next sleep cycle or reboot. Not sure where to go from here - open to any suggestions.
Edit: This issue bugged me for two full weeks. I even switched to i3 "cold turkey" in an attempt to escape from this effect, which worked until the first sleep/wake cycle.
Anyway, to anyone else in a similar predicament years from now - the problem was caused by autorandr, which I had executed to re-save my default profile while redshift was running. Apparently, autorandr saves not only the combination of active displays and properties such as resolution, but also their current color temperature. Another save of the default profile after the color temperature has been reset (xcalib -a -c) ultimately saved me from this red-tinted hell.
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