Item Tracking on the Transfer Order

NAV 2016. When I am creating a transfer order for an item with a serial order I want to fill in the Warranty Date on the Item Tracking line.

1. When I enter the Warranty date at the first opening of the Item Tracking line everything works fine and the Warranty Date is transferred to the Receipt Item Tracking Line.
2. If I forgot entering the Warranty Date at the first opening and reopen the already saved Item Tracking line, then the Warranty Date is not transferred to the Receipt Item Tracking Lines.

Looks like a bug to me. Have someone encountered this? Do you have a shortcut of how to fix it. The code does not look very straightforward.

Thank you