A person can say shniyem mikra of the next week shabbos after mincha. Does this mean after mincha time, when you actually daven mincha or when your community prays mincha?
As implied by the Tur (Orach Chaim 285), it means that time when it is possible to daven mincha, meaning the time of mincha gedolah. At this time, we move on to next week’s parashah. Shnayim mikra should therefore be finished (preferably) by the time of mincha gedolah, and from this time and on one may begin the shnayim mikra of next week’s parashah.