I guess sheet film support requires another master roll and they've seen things being a bit slow. Maybe they are doing it as a probe for the response. Seems utopian, but maybe they could pass sheets to a Ulford ULF type run.
As of superia, and as I said in a couple of threads, there was a sort of packaging/formats rationing of the line in the US recently. Basically some blisters were discontinued and replaced with single roll or another blister type. That's from top of my head and I can't for the life of me find the original source of that.
But the case is that it would be curious to do a packaging reorganization to discontinue 6 months later.
OTOH, Natura 1600 was not supposed to be discontinued for a couple years already? We may be seeing regional distribution choices too. Just as 160NS is 120 + Sheets only and EU, Asia distributed. Weird really. So last year Asia had this product (160NS) in 120, 220 and sheets -- US? None at all.
Oh, that probably is Portra 400! Plenty of happy people shooting the film at low EI's, pushing while doing the former too, just pushing, and shooting at a higher EI than box without push.
I think the independent online labs are doing a good enough job with processing that they seem to be quite sucessful and in the last 4 years have grown quite a bit.