What is demarcation line between 41 week + 6 days

what is demarcation line between 41 week + 6 days (late preterm) and =/>42week (post term) if wee see daywise in a week?

complication of post term labor

Macrosomia weight of baby >4 kg leads to

Prolonged labour
shoulder dystocia
increased changes of cesarean section

Oligoydramnios cord compresssion fetal distress meconium aspiration syndrome variable deceleration on CTG

Placental ageing - Uteroplacental insufficiency-fetal distress late deceleration of CTG

Isn’t it late term around 41 wk +6 days instead of late preterm