I've noticed this, too (Lulzbot Taz 4).
Printing thin strips 110 x 3mm with cylindrical "bolt heads" which should be 0.8mm high for the strip, and 0.7 for the "bolt heads". There are no sloping verticals. With 0.25mm 1st layer, and 0.12mm other layers, slicing with Adaptive Layers ON, only has 6 layers - 3 + 3. and is only 1.2mm high (the strip itself is only 0.54mm thick. The layer height doesn't seem to have been varied, there are just less of them
Without Adaptive Layers, there are 10 layers, 6 + 4, and the print is just over 1.4mm high.
I've just been back to Cura 4.0 and re