C:\COBWEB> type flies.log

FLIES CAUGHT: 0

A fly = a lot sold before it reached full weight. Nothing is taken from it: it just stops earning silk, and the silk stays with the holders.

Missed silk is an estimate (rule 7): what the lot would have earned at full weight to the end of its epoch, minus what it earned. Fonts: VileR, int10h.org, CC BY-SA 4.0.