I built a solid oxidizer tank, set it to 579Kg max, built an oxylite production facility, and my dupes started to fill it as expected. However, they didn't stop at 579Kg of oxylite, they kept filling it past that to 599kg, and the Errands tab for the tank shows them still trying to insert more, despite it being full.
Build rocket with solid oxidizer tank.
Set max tank size to be less than the max
Have dupes fill oxidizer tank
Observe as dupes overfill it, past the amount set in the tank's UI.