In Keen 4-6, switches can extend or reduce the range of moving platforms. Internally, this works by inserting or removing the infoplane value that renders as a B block in level editors. The switch-flipping routine first checks whether there's a pathing arrow (by testing the tile ID range), and if there isn't one, it just XOR's the current infoplane value with 0x1F, the ID of the B block. When that happens on a link value, it has the effect of flipping the last five bits of the Y coordinate.
Therefore, it's possible to change a door's destination with an infoplane switch, but only vertically and only to certain Y coordinates. Somewhere online, there used to be a neat guide on setting this up, but it appears to have been lost and I cannot find an archived copy. I might write a full new one sometime.
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