This segment you speak of is part of and called the UP Tracy Subdivision. It extends from just east of the current Amtrak Stop at Martinez called Ferry to a connection with the UP Fresno Subdivision at North Lathrop. For those that have ridden and/or saw any of the Coast Starlight detours that turned their train at Lathrop, techinally they used the East most 1 mile of this line for turning the train. If should be noted that back in the SP days, these were two separate routes to Tracy, but that UP came along on paper years back and "spliced them together" to form the current Subdivision with the limits I mention above. Between the Control Point at Port Chicago (this is where the Amtrak San Jauquin Trains come on/off the BNSF) to a Control Point a couple miles East of Tracy, this territory is Dark, controlled by TWC from the Dispatcher in Omaha. Yes, it is in service, but doesn't see any kind of through traffic. The UP has no intentions of ever selling this line because it is a through, mailnine route, that can be fixed up and put to use again at any time. As I remember it, the ABS was never retired by SP, just left in place. But because of little or no use at times in certain places, it was vandalised, parts of it stolen and salvaged. As a reult, this signal system could never but put back together as is, so (I can't remember if it is under SP or UP, I think UP) applied to retire it and for the reasons stated above, it was officialy retired. If the line ever gets used for through traffic again, I don't see UP spending the money to install ABS or even CTC on it. I do see them raising the speed for Freight Trains to 49 (once track work is done). Supposedly there are long term plans for this entire line, but I don't know what they are. Unless the road crossings devices are taken out of service, and this would only be because of malfuntion or something broken with the crossing, then all X-ing Warning Devices have to be tested on a scheduled basis set by the FRA. This is why the crossings look good. Even if a train hasn't been over the X-ing in years, if the line is indeed in service, the devices have to be tested/maintained. Hope this explains it.