A is the leeward boat overlapped with B on entering the circle on a beat, both on starboard. The wind heads (or not?) so neither boat quite lays the mark on starboard. Both tack onto port 1 length from the mark. A's overlap is broken but he's tight on B's port quarter. Q1. Does A retain the right to water? Q2. If B tacks onto starboard to round the buoy does he need to give A warning & time to respond (including water to also tack round the mark or to sharply bear away)?   (I find nothing suggesting A loses his right to water just because both tack).