Dear Brady,
The owner of the lab I get my slides processed at (his business is mostly just E-6 developing) told me that Fuji had already shut down their production lines for their slide film and are just selling off old stock. When they run out they'll fire the lines up again, make a few batches, and shut down again, probably raising the price as much as necessary to sustain that kind of operation, but leaving it very vulnerable to the ax if they decide it isn't worth it.
your lab owner is misunderstanding what is normal and standard production method in film production: Film production is
not like e.g. car production where each model has its own production line and is produced every day.
Film production is very different: It is batch production. A (bigger) batch of a certain film (or photopaper) is coated, and the produced master rolls / parent rolls / Jumbo rolls are then cold stored. And from these cold stored rolls in the following weeks / months / years then the film will be converted / finished to 135 / 120 / sheet film. When the stock of cold stored master rolls is depleted, a new batch will be made (emulsion) and coated.
And the time between new coating runs is quite long. Example: Even at peak film sales in 1999 / 2000 Agfa (Leverkusen, Germany) coated BW film and paper in a 1.5 year schedule. So 18 months between coating runs!
That was and is just normal business at film manufacturing plants.
Lots of films (and BW photo papers) we use today are coated in 2 or 3 year schedules. It's just standard current business in the industry.
I visited the Harman technology / Ilford Photo factory in Mobberley in 2013 (Simon Galley being our tour guide; Simon, you are missed!). At that time only on three days per month the coating machine was operating (and then in a 3-shift 24h mode). The rest of the month: no coating. But of course finishing of products.
As since then the demand for Ilford film and paper has increased (confirmed by them), they may be running their coating machine perhaps 4 days per month now (but that is a guess).
And there are no separated "colour negative film lines" and "reversal film lines" and "BW negative film lines": Kodak is coating all its films on one coating machine. The same is valid for Fujifilm. Ilford, Foma, InovisCoat and Adox are even coating film and photopaper on the same machines (Kodak Alaris RA-4 silver halide photo paper is coated by Carestream for Kodak Alaris; Fujifilm has its own separate RA-4 production plant in Tilburg, Netherlands. The annual RA-4 production volume is much bigger than the annual film production volume).
The higher the demand, the more often coating runs are made. Look at the excellent film documentation about Fujifilm: Their finishing line for Instax is running 24h a day in 3 shifts. To "feed" such a huge production volume you need several big coating runs a year for the colour negative film base used in Instax films.
This is why the return of Ektachrome has me worried that it will lead to Fuji pulling out of E-6 altogether,
Don't worry too much. That is very unlikely, because of several reasons:
1. Reversal films are not homogeneous products. They are not identical, they have all different characteristics. Fujifilm told me that the production stop of Ektachrome in 2012 has not influenced their sales very much. Surprising? No, because
- those who used Ektachrome in 2012 were mostly Ektachrome lovers: They have tested Fuji reversal films in the past, but preferred Ektachrome
- and these real hardcore Ektachrome lovers filled their fridges and freezers with Ektachrome stock for several years and continued using it; that is the majority of the user base
- those who don't loved Ektachrome so much switched to either negative film, Fuji reversal or digital.
If now Ektachrome comes back, mostly the former hardcore users will use it again (lots of the fridges are probably now empty

).
And certainly also some of the young guys which are now discovering film the first time in their life ("digital natives") will try it (and Fuji and Film Ferrania reversal film, too).
They are a very important factor in the film-revival.
2. We see an increasing demand for BW and professional colour film in the main film markets. Why should all these films rises in demand, and only colour reversal film decline in demand? Quite unlikely. The tide raises all boats.
Especially if we start a good marketing for reversal film again. From my numerous talks with Dave Bias I am convinced Film Ferrania knows the need for that and will do it. And the first activities of Kodak in January concerning Ektachrome let me hope that even Kodak has understood the unique advantages of reversal film and the necessity for a proper marketing of them.
3. Those who love Provia and the Velvias will continue to use them. Ektachrome or the new FF film are very different and cannot replace the Fujichromes. They are unique.
I've recently talked to Fujifilm film representatives and they told me that they continue reversal film production.
There is a really good chance for a sustainable long-term film-revival that also includes a sustainable reversal film revival!
It is in our hands!!
Just let's do it!!
Shoot more reversal film, show your brillant results to other photographers and motivate them to start using it, too.
Best regards,
Henning