Driving through Fort Worth, Texas on I-35w, there is considerable road construction. Scattered through this construction there a bunch of those text-messaging-devices that are immune from the Texas Department of Public Safety laws prohibiting texting while driving and especially texting or even using your phone in a construction zone. They say something like,
No Texting while driving
or
This is a no phone zone
and inform you that in the construction zone fines are particularly heavy.
One particularly not-so-helpful sign said,
Various lane closures at 9 pm
so that the reader would know that at 9pm that some portion of I-35w was going to become the vehicular version of Whac-A-Mole.
Ever the traveler, your grumpy Uncle Dave.
The Free Dictionary by Farlex. https://idioms.thefreedictionary.com/whack-a-mole