I like the idea of recording time. Making the arm turn off the switch with the longest recorded time. just need some code
Ask and ye shall receive:
unsigned long switchTurnedOn = millis();
Of course, you probably want an array, but that's easy enough. And, you probably want to set the ith element of the array, but that's easy, too.
int DcMotorAcc = map(DistanceAcc, 0, 250, 255, 255);
is identical to:
int DcMotorAcc = 255;
but consumes far more resources, so an explanation is is order.
if (digitalRead(Switch1) == LOW && (LastSwitch1) == HIGH && (FakeSwitch) == LOW)
(Why) (are) (the) (variable) (names) (in) (parentheses)?
Personally, I like to use Pin and State in variable names, so pin and state variables are clearly distinguishable.
It's hard to see how much of your code is involved with moving the carriage right or left, or how the program has moved the carriage to the correct position.
It's hard to see how much is involved with turning the switch off,
Put the code to move the carriage into a function taking one argument - the number of the switch to turn off or 0 to return to home.
Put the code to turn a switch off into a function taking no arguments.
Create a function to turn a switch off, taking one argument. When it is time to turn a switch off, call that function. It will be easy to extend the program, then, to deal with multiple switches.