BellBoard

1342658709E   1   2   7   9   18   19
-------------------------------------
12346587E90            (a)
2413                  S       -             |
4321                  S       -             |
3142                  S       -    SS       |                      
1324                  S   S   -             | A
3412                  S       -             |
4231                  S       -             |
2143                  S       -    SS       |
-------------------------------------
123465E7098       -   S   S   -
214365E7908   S         A
-------------------------------------
1234657890E            (b)
21436578E90   -         A
-------------------------------------
1234658790E            (c)
2143658709E   S         A*
-------------------------------------

Round in one change

A* = A, omitting all singles at 19

Start at backstroke with rounds as the third row of a slow six

(a) = 3.s4.s6.7.s11.12.14.16.17.20.s23.s25.26.28 (28)
(b) = s7.s9.s13.s15.18
(c) = s7.9.10.s13.s15.18.22