It does same in mine, maybe a tiny bit down. At what position the low-fuel light starts blinking? In mine, at about half of last quarter it slow-blinks few time then if I keep driving on, it keeps on permanently until refueled.
Only few times fuel was filled to the neck, usually I ask the attendant at fuel pump to full tank on auto stop. When filling is auto stopped, I ask to round up the payment to 100.