The requested example as a survey file.

Strangely : javascript ( {self.NAOK} ) show a good value

Think it's a boostrap-datepicker issue (see screenshot) BUT : https://github.com/smalot/bootstrap-datetimepicker/issues/3 is closed.

16:00 pm is clearly an invalid date

It's our integration of datetimepicker : https://eonasdan.github.io/bootstrap-datetimepicker/ is OK (see first)

Capture du 2017-03-18 20-26-12.png (7,048 bytes)   

Capture du 2017-03-18 20-26-12.png (7,048 bytes)   

https://github.com/LimeSurvey/LimeSurvey/pull/669

You know better momentjs than me. We have to restrict momentjs for php control of date

PHP control is done here : https://github.com/LimeSurvey/LimeSurvey/blob/master/application/helpers/expressions/em_manager_helper.php#L8704
And don't accept other momentjs part. And more : using only momentjs broke existing survey.

https://github.com/LimeSurvey/LimeSurvey/pull/669

Fix committed to master branch: http://bugs.limesurvey.org/plugin.php?page=Source/view&id=22482

Prior to the 170324 release I was using the datepicker successfully with the following settings:
format: dd-mm-yyyy
Minimum date: "-6 months"
Max date: "now"
After the upgrade I noticed the datepicker validation broke with these settings - selecting dates above the max worked unexpectedly, but odd things started happening with the selected month.
To fix the issue in 170324+, I removed the format setting.
You can reproduce these settings working with 170310

https://bugs.limesurvey.org/plugin.php?page=Source/view&id=22508

Refixed here : https://github.com/LimeSurvey/LimeSurvey/commit/8b5d809d566b3db9473445818d8b30938a699ea4

Release 2.65.1 Build 170522