In 2009, Monmouth County assumed jurisdiction of the southernmost  of Sharon Station Road between CR 539 and CR 526 as a part of an overall project to allow through traffic on CR 539 to bypass Allentown. Monmouth County has designated this road County Route 539A although the route became signed as CR 539 Alternate  between CR 539 and CR 526.
In 2009, Monmouth County assumed control of a section of Sharon Station Road between CR 539 and CR 526 to improve traffic flow on CR 539 by diverting it around Allentown.  Monmouth County designated this road as County Route 539A; however, the route was later marked as CR 539 Alternate between CR 539 and CR 526.