All double lessons can be over certain break

All double (or longer) lessons are forbidden to be over breaks created in the "School - Bell times - Periods" dialog from the default.
=Cómo puedo especificar Recreos largos/ Recreos de la comida
It means, that such long lessons must either finish before or start after this break. It is useful, if you define breaks as "Recess" or "Lunch" and you probably do not want to be in the middle of the double Chemistry laboratory lesson.

However, if it is no problem for you, and all your double lessons can be over specific breaks (e.g. the break is too short and kids will have individual breaks before or after the double lesson), simply turn off this constraint for the break. In "Periods" dialog select the break - click Edit - and uncheck the option "Double lessons cannot span this break" in the bottom of the dialog.

Note:
- all double lessons which are over not allowed break are marked with the "red" strip. Unchecking mentioned option above these trips will be removed.
- you can switch this options off only for the longer lesson for particular subjects in this way:
Lecciones dobles no pueden impartirse durante "recreos largos"