Another area that might affect travel time is the junction with Metro North New Haven line at New Rochelle. This is a flat junction and subject to delay due to conflicting moves. I imagine this could get worse when MNCR starts running to Penn Station. At one time there was talk of building a flyover here is that still a possiblity?
FRA originally planned a flyover junction. It was determined that the real estate needed for the flyover alternative is not available. It involved moving too many things including an entire cemetery, which was not going to happen without going through litigation that would last decades if not centuries and cost way too much
Instead the flat junction was modified at CP216, with complete realignment of flow through New Rochelle station and moving the full merge of Amtrak flow into MNRR flow to the east of of New Rochelle station through high speed switches at new CP217. Additionally Amtrak created two new interlockings on the Hell Gate Line, CP 215 and Manor, to preposition trains on the correct track.
This raised Amtrak speed through CP 216 to 45 mph from the previous 15mph. MNRR has a 40mph speed through CP 216. It reduced Amtrak's running time through CP 216 by 1.5-2 mins.
The realignment moved the conflicts east and spread them out over a couple of interlocking providing alternative paths to the dispatcher using high speed (track speed 70mph) crossovers instead of the previous 15mph ones. The current layout is considered to be adequate for MNRR to Penn Station, and currently no further changes are planned.
Eventually if the NEC Futures high speed plan comes to fruition it will not touch this area. It will be left as is for local and regional traffic. The high speed line will use a separate two track alignment possibly through lengthy tunnels in this area.