The current (new since a few yrs) JB big stesyen is integrated in the giant border-check facility (must be one of the most used in this world-similar to between HKG and mainland CHina in normal days without Corona). The land under the tracks in SIN is (what I somehow remember) owned by the Malay KTMB or maybe even the Malay govmt.-hence they could make a very big profit when they sold off the old SIN stesyen and line into it.
There are long-term plans to extend SINś MRT also over or beside the causeway into JB this would obviously remove the need for this last short sector and the shuttletrains. Maybe the big loss in revenue (paying MYR and not SID, but same amounts in nr) whereas all costs are in SID, has a role.
The old JB stesyen building was till standing (empty) when I recalled-but may have chnaged, its now a few yrs ago since I was there last. Probably some kind of listed status or so.
On skyscrapercity (strange name, but also has a very big railway section on latest news, building etc. on trains on rails in this world) there is a recent report on the double tracking and electrification of the last sector south of Gemas. Looks like a complete rebuild.
There are all kind of rumours and debates as KTMB also plans to build a direct link from KUL into the east-coast, also linking up to a few bigger cities there still without trains, avoiding the large loop via Gemas to reach it.
Ie done that east coast rwy a few times-overnight, and a few short sections daytime-IMHO grossly overstated as to the assumed jungleness. But if youve never ever seen or been into ´jungle´ it might be interesting. The short local all-stops are a living museum (or dump?) of the last remaining KTMB old stock.
