My school has 3 hours and 45 mins of MX1 classes per fortnight and 4 hours of MX2 classes per fortnight. Thing with MX1 class is that the 2U class and MX1 class is the same, so we finish one topic fully (whether it is 2U or 3U stuff), not worrying about what class it is. So that's just the official numbers.
About 6 MX1/2u lessons a week (we stay in our 3u class and just cover whatever)
And 2-3 MX2 classes a week either in study periods or at lunch time (dont think the teacher likes before or after school)