When it had 6 lanes it had to be a long while back. As far as I remember, when I lived there anyway, it was always 4 lanes from Exit 14 to 14C and the free part to the Holland Tunnel ( Jersey Avenue). However, it was not until either right before I moved to FL in 1990 or after I moved here to FL and visited home, I noticed that there was full shoulders which struck me odd as most bridges of that type feature none usually.
I am guessing it was once 3/3 and then dropped to 2/2 at 14A at one time. Though even the Passaic River Eastern Spur and Hackensack River Eastern Spur were originally 2/2 with the piers underneath the structure to show that. When they did the work on it I remember it was long after the Western Spur opened as well. So it is odd that the extension had one more travel lane each way than the mainline it stems from as originally even the 3/3/3/3 were at 2/2 when the Turnpike first opened.
However, stranger things on roads have happened.