Blue shall be penalized. When Red reaches the zone she is clear ahead. According to rule 12 Blue shall keep clear and according to rule 18.2(b) give mark-room to Red. After getting a leeward overlap Blue shall give still room mark-room to Red according to rule 18.2(c). Red is breaking rule 11. Because Reds proper course is close to the mark, she is sailing within the mark-room, she is entitled, and therefore she is exonerated by rule 21. Blue shall be penalized for breaking rule 18.2(b).