I would only add to Bob's sage advice. I visited the area in 2011, the last really heavy snow year, after a 46 year absence. I followed the Post Creek Trail without incident from Isberg Pass to the Rutherford Lake / Fernandez Pass 4–way junction (seen at approx.1:39 in my pre GoPro video of the trip
https://www.youtube.com/watch?v=x_BlYWIdX_k), where the trail clearly continued downhill a couple of miles to the the "California Riding & Hiking Trail" (?) and other intersections leading to the Fernandez Pass Trailhead. The NGS map was recommended to me as being "most" accurate by Rangers when I got my permit. I found it generally concurred better with my faded, corner worn 1950's USGS quadrangle than any of the newer maps. They also advised that only a few of the lower Clover/Soldier Mdw. trails and Isberg had been cleared of massive downfall at that late date.
That said, the area has a lot of confusing intersections and trails, made all the more so by dense forest below 9,500 feet or so. My Yosemite Trail rule applies here as well as any. Any trail either not used commercially by pack stock, or within a mile or two of habitation is likely to be in poor repair and/or suspect.