I don't know what this is called or what the source of the problem is, but when I print in abs the last couple of layers are not printing right. I would see holes or gabs in the last couple of layers.
You may want to download the desktop version of cura and try slicing with that (octoprint uses the cura engine for slicing but you don't have nearly as much control over it). You'll be able to tweak all kinds of things, including how many top solid layers there are.
I am liking this slicer, real nice. The thing is I am still in the testing phase. I finally got the new setup tuned so that cura is working with my duplicator properly (last issue was the diamater).
Initially I avoided it because I thought it would only work on ultramaker machines