Flashforge Adventurer 3 crack printed same height every time

[curious aardvark]

you're actually printing quite fast for abs, and fairly cool as well.
And the reason it takes so long is because you are using very thin layers.
3d printing is NOT fast :-)
Patience is your best friend - also so is PLA.

It could simply be that at that height the abs has cooled suffciently to shrink.

Have you tried omething simple like a simple column ? and see if that does the same thing at the same height.

Given how the rest of the model looks - it doesn't look like abs shrinkage. And it's unlikely to be an issue with the printer.

resize the attached cube to be as tall as the model and, maybe 15mm square. and see what happens. You can resize it with flashprint.
Also get some pla and try that.