Finally got around to putting it together. Hope this helps.
Adjust Date.kmmacros (20 KB)
And a decrement version…
Keyboard Maestro 8.0.5 “Adjust Date [down]” Macro
Adjust Date [down].kmmacros (20 KB)
https://drive.google.com/open?id=1MDE70hM7gHPQnzByireWtefnntjFf66O
This is awesome. Thank you @dashard
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