You can use a permanent substitution when a teacher is absent for long period of time. The cover teacher is allocated a certain period in the timetable (e.g. Mo-2) for all the weeks that his/her colleague is absent.
Example:
Teacher Cervantes will be absent from 26/09 until 10/10. We can now look for a suitable teacher to cover for him for class 2b's biology lesson, Mo-2.

When we open the substitution proposal we see the option of checking 'Permanent substitution'.

Using this option you can allocate the substitutions on all Mondays, second period to e.g. Maria Callas.
