Created attachment 2918 [details] error box with due date When you choose a due date in the past a box appears asking you to confirm the date. This box should have a calendar icon and a date format tip like all other date boxes in Koha to prevent big mistakes.
We might also want some text to say 'you chose a due date in the past. are you sure?' Right now the box is there, but no explanation.
CanBookBeIssued should be altered to differentiate between Invalid (i.e. badly formatted or non-existent) and Past due dates. This will allow for different confirmation boxes to be presented to the user with distinctly different text.
This is still an issue in master.
This appears to be fixed now.