Building or demolishing buildings or wires with automation capabilities will update your automation time by one tick.
We recognize that this is a game mechanics that many people who have played with automation in the sandbox are aware of.
So this is fine in itself, but there is a problem that the advanced mode of the signal counter does not properly support this mechanism.
The signal counter on the right is in normal mode and the signal counter on the left is in advanced mode.
As you can see, the signal counter in advanced mode cannot properly respond to automation updates during construction / demolition, and outputs a signal of 1 tick or more.
This was paused for clarity, but of course the same thing happens with normal real-time duplicant construction / demolition.
An obvious problem is when combined with an XOR toggle circuit that relies on a 1-tick signal.
In this way, the state of the XOR toggle was orderly at first, but due to the overlapping timing of construction / demolition by the duplicant, a 2-tick signal was transmitted, and the state of the XOR toggle went wrong.
This means that automation systems with precise tick control can have problems.
Of course, to avoid this, you can do it by adding a logic gate to make the signal 1 tick, or by not using the advanced mode in the first place, but that makes the circuit a little redundant.
The advanced mode of the signal counter is an easy-to-use feature. So if this is an unintended bug, I hope it will be fixed someday.
As shown in the video above.