BellBoard

1234567   1 2 3 4 5 6 7 8 9 0
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1274653     S   S -   - -   -
6124537         S   -   -    
2145763   -   -   -     S   -
6135724   S     -   S -   - -
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21-part

In parts 4, 7, 10, 13, 16, 19 call course two s2 (2) and then continue with course three

In part 1 call course two s4.6.8.s10 (10) followed by five courses called s2.4.6.s8 (8) and then one course called s2.4.6 (8). Then continue with courses three and four to bring up part end 2461357

For cyclic part ends start with rounds as the sixth row of a quick six (Erin start)