But my question is that if Schedule Lines option is available during PO process then it should show accordingly during MIGO process...
You can see schedule in the PO ,But when you do goods receipt it will show open qty of the PO.In that case use ASN (Inbound delivery) Functionality.Ask the vendor to submit the ASN based on your schedule date.
Do the GR based on Inbound delivery,So that it will not show Complete PO qty .It will only show Inbound delivery scheduled qty.