Six observations per day, conservative approach day observation sequence source days observed note twice once 1 A B C A B D ab A 3 1 fiducial 2 A B E A C E a B 1 3 fiducial 3 A B F D B F b C 0 3 primary 4 A B D A C E a D 0 2 primary . A B D A B E 1 1 secondary F 1 1 secondary day observation sequence source days observed note twice once 1 A B C A B D ab A 3 2 fiducial 2 A B E A D F a B 3 2 fiducial 3 A B E C B E be C 0 3 primary 4 A B F A D F af D 0 3 primary 5 A B E C B F b E 1 2 secondary . A B E A F F 1 2 secondary day observation sequence source days observed note twice once 1 A B C A B D ab A 4 2 fiducial 2 A B E A F E ae B 3 3 fiducial 3 A B G C B E b C 0 3 primary 4 A B F A D F af D 0 3 primary 5 A B G C B G bg E 1 2 secondary 6 A B E A D F a F 1 2 secondary . A B G A B G 1 1 tertiary day observation sequence source days observed note twice once 1 A B C A B D ab A 4 3 fiducial 2 A B E A F G a B 4 3 fiducial 3 A B E C B E be C 0 3 primary 4 A B H A D H ah D 0 3 primary 5 A B F E B F bf E 1 2 secondary 6 A B G A D G ag F 1 2 secondary 7 A B H C B F b G 1 1 tertiary . A B G A H H 1 1 tertiary day observation sequence source days observed note twice once 1 A B C A B D ab A 5 3 fiducial 2 A B E A F G a B 4 4 fiducial 3 A B H C B H bh C 0 3 primary 4 A B F A I F af D 0 3 primary 5 A B E D B E be E 1 2 secondary 6 A B G A C G ag F 1 2 secondary 7 A B I E B I bi G 1 1 tertiary 8 A B F A D H a H 1 1 tertiary . A B G H B I 1 1 tertiary day observation sequence source days observed note twice once 1 A B C A B D ab A 5 4 fiducial 2 A B E A F G a B 5 4 fiducial 3 A B H C B I b C 0 3 primary 4 A B E A D E ae D 0 3 primary 5 A B G J B G bg E 1 2 secondary 6 A B I A F I ai F 1 2 secondary 7 A B H C B H bh G 1 1 tertiary 8 A B F A E F af H 1 1 tertiary 9 A B J D B J bj I 1 1 tertiary . A B G A H J 1 1 tertiary day observation sequence source days observed note twice once 1 A B C A B D ab A 6 4 fiducial 2 A B E A F G a B 5 5 fiducial 3 A B H C B H bh C 0 3 primary 4 A B E A I E ae D 0 3 primary 5 A B G D B G bg E 1 2 secondary 6 A B I A J I ai F 1 2 secondary 7 A B K H B K bk G 1 1 tertiary 8 A B F A C F af H 1 1 tertiary 9 A B J E B J bj I 1 1 tertiary 10 A B F A D K a J 1 1 tertiary . A B G H B K 1 1 tertiary day observation sequence source days observed note twice once 1 A B C A B D ab A 6 5 fiducial 2 A B E A F G a B 6 5 fiducial 3 A B H C B I b C 0 3 primary 4 A B E A J E ae D 0 3 primary 5 A B G D B G bg E 1 2 secondary 6 A B F A K F af F 1 2 secondary 7 A B L C B L bl G 1 1 tertiary 8 A B H A F H aj H 1 1 tertiary 9 A B J L B J bj I 1 1 tertiary 10 A B I A E I ai J 1 1 tertiary 11 A B K D B K bk K 1 1 tertiary . A B G A H L 1 1 tertiary day observation sequence source days observed note twice once 1 A B C A B D ab A 7 5 fiducial 2 A B E A F G a B 6 6 fiducial 3 A B H C B H bh C 0 3 primary 4 A B I A F I ai D 0 3 primary 5 A B G J B G bg E 1 2 secondary 6 A B E A D E ae F 1 2 secondary 7 A B K L B K bj G 1 1 tertiary 8 A B M A C M am H 1 1 tertiary 9 A B H I B K b I 1 1 tertiary 10 A B F A M F af J 1 1 tertiary 11 A B J E B J bk K 1 1 tertiary 12 A B L A D L al L 1 1 tertiary . A B G H B M 1 1 tertiary day observation sequence source days observed note twice once 1 A B C A B D ab A 7 5 fiducial 2 A B E A F G a B 6 6 fiducial 3 A B H I B H bh C 0 3 primary 4 A B J A C J aj D 0 3 primary 5 A B E K B E be E 1 2 secondary 6 A B I A F I ai F 1 2 secondary 7 A B L D B L bl G 1 1 tertiary 8 A B G A M G ag H 1 1 tertiary 9 A B N H B N bn I 1 1 tertiary 10 A B J A C L a J 1 1 tertiary 11 A B K E B K bk K 1 1 tertiary 12 A B M A N M am L 1 1 tertiary 13 A B F D B F bf M 1 1 tertiary . A B G A H N 1 1 tertiary day observation sequence source days observed note twice once 1 A B C A B D ab A 7 5 fiducial 2 A B E A F G a B 6 6 fiducial 3 A B H I B H bh C 0 3 primary 4 A B J A C J aj D 0 3 primary 5 A B E K B E be E 1 2 secondary 6 A B I A F I ai F 1 2 secondary 7 A B L D B L bl G 1 1 tertiary 8 A B G A M G ag H 1 1 tertiary 9 A B N H B N bn I 1 1 tertiary 10 A B O A E O ao J 1 1 tertiary 11 A B J C B L b K 1 1 tertiary 12 A B K A N K ak L 1 1 tertiary 13 A B M O B M bm M 1 1 tertiary 14 A B F A D F af N 1 1 tertiary . A B G H B O 1 1 tertiary