Seems like group ABC is kick it well for the last 10 draws.
A: numbers from 1 - 14.
B: 25 - 28
C: 29 - 42
and of course Mega Ball group C: 24 - 35
This will most likely be active group for at least two more weeks, then it will change. Before it change to another groups there will be an extreme odd case of appearance of number groups, like "BD" on dec 15th. That was the indication of a new change, which came on with ABC. Look for a new crazy group to show up, AB/AC/AD/BC/BD/CD or 2 - 3 consecutive ABCD to show up then there will be a new set of numbers to lock onto.
As far as the Mega Ball goes, look for group D: 36 - 46 to be active the rest of this and next week, then it will kick to group A and B, and back to D again.