The bug is that, if an arrow is stuck in the positive x/z side of block, the caret coordinates do not work. The position is wrong if you use the arrows position in the command and the rotation is also off.

I found this when I worked on a rework for a block_surface_detection. Since the x,y,zTile-data was removed, I had to come up with a new concept.
An arrow is always the same distance apart from the point of the block it is stuck in. (0.045..0.0499) Anyway, when I worked this out and tried it I noticed that only if the arrow is stuck in the northern or eastern side the command will fail.

The picture is reproduced:
The used command to summon the aec was "/execute as @e[type=arrow,limit=1] at @s run summon minecraft:area_effect_cloud ^ ^ ^0.045

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