The MOB line Zweisimmen – Montreux (the true Golden Pass line) is operating normally for the 2019 season. There was engineering work earlier this year on the MOB line but engineering work is usually carried out in the ‘in between’ season, and also in spring or summer, not in winter.
Nowadays as a ‘disclaimer’ they state reservation is recommended, but I’ve never reserved a seat on the MOB line nor any other Swiss train and have never not been able to travel on the train I want. In general Swiss trains run frequently enough to take up all the possible demand.
For a number of years the MOB operated ‘Crystal Panoramic’ services with ‘grand view’ front and back end observation cars. They have now stopped this practice, and taken the ‘VIP’ seats off sale and removed the reference to them on the timetables. This is because they have replaced the old rolling stock with new stuff, this means that the power cars may be located at the outer ends of the train, so the Observation cars don’t work (the VIP seats used to be in observation cars at each end with the locomotive powering the train in the middle of the train.)
To clarify references to MOB etc, here follows my standard saved ‘FAQ’ that I have ready to paste for questions about the ‘GoldenPass’ route
Current tourist branding can be confusing
The ‘Golden Pass’ is marketed nowadays as Luzern – Interlaken – Montreux, but the Luzern – Interlaken railway is actually the Brunig Pass (the true Goldenpass is just the MOB railway Zweisimmen – Montreux).
A few facts about the Montreux – Zweisimmen railway – ie the MOB (Montreux-Oberland Bernois):
The Golden Pass is historically only Montreux – Zweisimmen, only more recent marketing branding takes the ‘Goldenpass route’ east of Zweisimmen to Interlaken and beyond to Luzern.
The Golden Pass is the touristic branding for the Montreux – Oberland Bernois (MOB) railway which runs from Montreux to Zweisimmen, but after a few years of favouring ‘Goldenpass services’, the company decided it was losing its tradition and has reverted to putting the Chemin de Fer Montreux – Oberland Bernois name on publicity and train coaches.
MOB pioneered the Panoramic coach concept on Swiss trains, starting in 1976.
There are now several versions of panoramic coaches in service, but MOB keeps changing its mind how to dub each service.
It hardly matters anyway as most modern Swiss trains have large windows, even if not officially panoramic. The key element of a ‘panoramic’ coach is ‘toplight’ windows above your head but in practice very few of the major views from panoramic trains are directly above your head, so the view through the normal side part of windows is normally fine.
I recommend using regional trains on the MOB (the real name for the Montreux – Zweisimmen railway). Again, this gives you the flexibility to get on a train at whichever time suits you.
If you do do the MOB railway you can catch any train, there is no need to book, and in fact you could pick it up anywhere along the line if you fancy.
Here is the timetable PDF for the MOB:
http://www.fahrplanfelder.ch/ fileadmin/fap_pdf_fiel ds/2019/120.pdf
It is very scenic, but the MOB route is far from being the most spectacular (although any dubbing of this nature is going to subjective and personal) in Switzerland.
The Luzern – Meiringen – Interlaken line is the Brünig pass line operated by Zentralbahn (ZB), which dubs the regular trains “Luzern – Interlaken Express’. Due to the geography of the area the lines from Luzern and Interlaken approach Meiringen from the same direction, so the trains must reverse direction in Meiringen station