Cup's schedule:
Here is the schedule for both CS OC Div1 and Div2. Please keep in mind that this schedule may change a little bit during the cup. You can see the maps that are going to be played in the group stage + in Div2 qualifiers from here.

OpenCup Division 1:
31mar - 7apr: Groups matchweek 1 (de_nuke)
7apr - 14apr: Groups matchweek 2 (de_cpl_mill)
14apr - 21apr: Groups matchweek 3 (de_dust2)
21apr - 28apr: Groups matchweek 4 (de_inferno)
28apr - 5may: Groups matchweek 5 (de_train)
5may - 12may: Week reserved for wildcarded matches & making playoffs
12may - 19may: 1st Playoffs round
19may- 26may: Quarterfinals
26may - 2jun: Semifinals
2jun - 9jun: Finals

OpenCup Division 2:
17mar - 19mar: Qualifier matches scheduled
20mar - 24mar: Qualifiers phase 1 (de_inferno)
25mar - 29mar: Qualifiers phase 2 (de_dust2)
31mar - 7apr: Groups matchweek 1 (de_nuke)
7apr - 14apr: Groups matchweek 2 (de_cpl_mill)
14apr - 21apr: Groups matchweek 3 (de_dust2)
21apr - 28apr: Groups matchweek 4 (de_inferno)
28apr - 5may: Groups matchweek 5 (de_train)
5may - 12may: Week reserved for wildcarded matches & making playoffs
12may - 19may: 1st Playoffs round
19may- 26may: Quarterfinals
26may - 2jun: Semifinals
2jun - 9jun: Finals

MaxRounds 15!