The freight that moves west on the SU-99's is blocked for three different destinations: NS Binghamton, CP(D&H) Binghamton, and CSX Syracuse. I'nm not sure which block gets placed in which order, but I do know those are the destinations for the westbound freight. Likewise, the SU-100 gets its freight from the same three interchanges, although with the recent NS/CP(D&H) agreement, there may be just one Binghamton block insyead of the current two. And it certainly seems like the CSX interchange is handling the lion's share of the traffic theses days.
I know I'm getting old... My insurance company sent me only half a calendar this year!