zwol | (Reply)

From:

There's a minor variation on on your second pattern that's reachable, though, starting from the first pattern. How about:

..............
....AA  BB....
....AA  BB....
..AA      BB..
....AA  BB....
....AA  BB....
..............

We got there from here (lower-case removed in the first round) by swapping the central pair:

..............
....AAbaBB....
....AAbaBB....
..AAbbabaaBB..
....AAbaBB....
....AAbaBB....
..............

And you can take out 8 more in the second round by putting matched pairs beyond the ends of the central column as well -- though I'm not sure I'm understanding exactly what you mean by "kingwise-connected":

..............
......AB......
......AB......
....AA  BB....
....AA  BB....
..AA      BB..
....AA  BB....
....AA  BB....
......AB......
......AB......
..............