What advantages do residence permits for a vocational and industrial training have?

The residence permit according to § 16 subs. 5 and § 17 Res.Act enables one to work up to 10 hours a week – even if the job is unrelated to the vocational training.
Can an adequate place of employment be found after successful completion of the vocational training, the possibility exists to have the residence permit extended for up to one more year.