The 3rd track project (so that there are 3 or more tracks all the way west from Hicksville / Divide should finish in the upcoming months. As I understand it, not only are all at grade crossings on that eliminated, there are also some improvements on connecting branches, rebuilt stations, the new (useless?) Elmont Station, piles of new tracks, signals, switches and power substations, some replaced (and usually a bit higher) bridges, better pedestrian access. So along the way, no one waiting for gates, less pollution, faster (believe it or not) schedules, a lot more capacity, and supposedly better or should I say the beginnings of reverse commuting service.
Lots of trains on the lines west of Hicksville. Using them are Huntington - Port Jeff Branch, the partly diesel only Central Branch (electric far enough to handle Ronkonkoma trains), and if needed, diesels from North Shore heading South. For instance, if everything west of Divide is shut down, a diesel can go from PJ to Hicksville, then east and south to Babylon, then go west on the 'south shore line to Jamaica, etc. Freight traffic uses the Montauk branch where it can, and typically goes anywhere else as it needs to but mainly outside rush hour.
I'm no expert, but I look at this to see how it will effect me!
The 3rd track project is finally not just underway but almost done after years of NIMBYISM, caused partly by poor planning and design. The 2nd Ronk track has been live for a while now. I've been waiting for ESA since 1996, expecting it to be done by 2006, LIRR says, I think, should have been done by 2009, might be open partially in 2022. LIRR / MTA has gone out of its way to make the draft schedules for GCT-LIRR (or Madison, since apparently Gov Hokum things it's only a service for people on Madison Avenue) as hard to compare to current reality as they can, and the more I hear, the more I wonder what will actually be working this year. It's also not clear what happens down deep under GCT in case of a power outage - there doesn't seem to be any sort of backup power other than for a few lights. They are finally dropping hints that they might soon be doing some sort of testing, but it's not, IMHO, clear.