Zone Time issue.
Most of the date are recorded with one day less.
For exemple :
A news has a start-date. This start-date is represented by a Date object. When we indexed it, this date lost 2 hours because of the zone time, so this date lost one day.

Moreover, the validation date is represented by a DateTime object. So the lost of 2 hours because of the zone time doesn't necessarily cause a lost of one day.

=> Create a lot of incoherence for the date indexation.