If I may ask a side question... does modern Ektacrome fade or turn blue as it ages? Any E4 or E6 I shot back in the 70's had all faded or turned blue, or both before the 80's were over. Anything Kodachrome, even from the 50's never degraded one bit.
I've been shooting Fujifilm Velvia (now Velvia 50) in medium format since 1997 - stored (some mounted in Wess plastic mounts, most unmounted) in archival PrintFile or Vue-All sleeves, in binders, at room temperature, in moderate-to-low humidity, all the while (same room in the same building, even).
The results? With some of my oldest mounted images (25-plus years of age, say) I have, for the past few years, begun to notice a very slight shift in the magenta direction. It is very subtle so far, and not noticeable unless comparing with an unaffected frame from the same original shoot. With my unmounted images, I notice no change of any kind.
The reason for the difference? I think it might be because the mounted images have their surface exposed to air more than the unmounted images, which are in contact with the archival plastic. But I'm not a chemist and I'm just supposing. (Its not the mounts themselves; if it were, I'd think the film surface in contact, or closer to, the mount plastic would be more affected than the film surface further away, but that's not the case. The magenta shift is even throughout the film surface.)
Anyway, other than this, there is no other degradation in any of the film, the oldest of which is now 28 years of age: no loss in contrast yet, no fading, no etc.
Take it for whatever its worth!