How long does one level of the German evening courses last?

The duration of one sub-level (ex: A1.1, A1.2, A1.3 and A1.4 - evening courses present 4 sub-levels per level) is approximately between 6-10 weeks. A complete level (A, B or C) takes between 24-40 weeks. However, it will also depend on each participant, how much time he/she will need.