Co to za zwrot?

Niedawno spotkałem się ze zwrotem "were due to".

Np.

1. Two more were due to vote late this week.

2. We were due to put one together.

3. These incidents were due to human error.

4. The city's schools were due to stay closed on Wednesday.

5. On Tuesday, May 14, the eggs were due to hatch.

Co oznacza ten zwrot, kiedy się go używa i jak przetłumaczyć te zdania?
1 2 4 5 - mieliśmy, mieli, miało (się)
3 - były spowodowane

jak widzisz, dwa znaczenia
zwroc uwage, ze w 3 nie ma bezokolicznika po 'to'