exseed

If they were to add express service on the SAS, they wouldn't necessarily need seperate express tracks. It is possible to run express services on a two-track line. There just needs to be a couple or so local stations build with bypass tracks so as to allow express trains to pass stopped local trains. Assuming the would get CBTC, the timing and coordinating of expresses passing locals shouldn't really be an issue.

(sorry for the late reply) It was on Gun Hill and Webster heading towards White Plains Rd.

I actually just saw a couple being transported eastward on Gun Hill Rd!