Information regarding schooling in Dutch language (Luxembourg)

Hello,
We probaly move to Luxembourg by the end of this year for a secondment of Protected content .

Since we have 3 kids (age 12,10 and 7) we would like to get in contact and/or receive information about the best approach for education.
The European school seems to apply only at the start of a schoolyear. We would like to know if alternative routes could be followed.

We are interested in the experiences of others.

Thanks in advance