I guess you can participate in this round since you will have 50 activity by the time you ask.
On another note, I read somewhere that the activity calculations were updated. Im not sure but assuming the old version is still being used, then its ok.
He may be able to participate, but according to the first post he may not get paid for those posts while he is bellow 50 activity:
EDIT: Due to the great number of complaints about spam bots, we will be restricting the next round (Jan 17th onwards) to users with 50+ activity. Any posts you make while you are under 50 activity will not contribute to your total.
