Hmmmm....
So, poking around Street View yields a couple things:
1) The end of Floral Park Rd at Livingston Rd was barricaded sometime between May 2009 and September 2012, and then formally deconstructed down to a bike/ped connection only sometime between then and August 2019.
2) That Begin north MD 223 shield linked above was installed sometime between May 2009 and August 2012. However, down at Livingston Rd,
this shield which implies a beginning of MD 223 further south was there in September 2012 and was still there as of August 2019.
This means signage is inconsistent, which in turn means the operating principle is to defer to what is on paper.
2018 HLR (most recent available) lists the terminus of MD 223 as "road end: barricade" and lists this as being on Floral Park Rd.
Ergo, a small adjustment is needed to move the endpoint away from an intersection that no longer exists (for motor vehicles anyway) to the dead end of Floral Park Rd. But a truncation of MD 223 back to where the begin sign is at Floral Park and Piscataway should not occur unless and until one of the following two things happens:
- the MD 223 shield on Livingston Rd is confirmed to be removed
- an update to HLR shows such a truncation
