the fact that this bundle currently offers a 0% discount is the living proof it's actually them manually fucking with it
here's what they do
>sale starts
>remove the non-sale bundle discount thus increasing the base price
>put on the sale discount
>sale ends
>put back the non-sale discount
they didn't do the last part this time

look at pic related
they didn't remove the normal bundle discount in time, thus the very first lowest dip
and then don't put the original discount back in time