Armor Stand Named Dinnerbone or Grumm don't go upside down

It's no NPC.

yes but it don't work for all entities? the armor stand don't have an AI but would be nice if it goes upside down when named this way :/

but would be nice if

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If you mess with the pose tag a little while, you'll be able to make the armor stand upside down

no you won't, you can't get the head down/the legs up above/below the body....
however, all MOBS will turn upside down, but a armor stand is not a mob