Recently I’ve noticed that when I run out af a color the new filament does not run all the way to the print head. At this time if you let it run out you end up with a line in your print, and the line does not have any strength. Did a helmet, 1.25 kg. lovely line on the top bit of the helmet, and i could probably squeeze it and the top would pop off. I should not have to predict when filament is going to run out, cut it off, let the remaining filament run through, pause the print, load the same filament in the same slot, ensure that it is actually extruding, restart the print. This is the process I know have to do to change filament mid print. And it has done it as well when auto-refilling. Flags waving!!
maybe try adding a filament change
Is it safe to assume you don’t have an AMS? if not the best thing to do is look at what you have on the spool, look at the estimate usage after you slice it, and have a filament change somewhere that makes sense, or just be there to swap a spool. The printer will use all it can, then let you know the filament has run out, prompt you to add more.
I am curious, did your helmet miss .25kg? I’m not sure how you could have done more than 1kg without changing a spool.