SS4 uses many sections of previous stages, but of course it never had this length. Start is near this intersection on the left road https://youtu.be/p_YeNVeJ5xc?feature=shared&t=157 Honestly, I am quite disappointed that the SS does not include this corner. But you can see the road quality there, the Friday stages are mostly run on a new smooth tarmac.
Most relevent onboard I found is this one: https://www.youtube.com/watch?v=UDK-Wcp8pQ4 The 0:00-3:50 section is run in the middle of SS4 in the opposite direction. In 2016, the road in the beggining had quite bad quality, but now it also has a new tarmac: https://en.mapy.cz/s/derefokuna