'restructuring' isn't meant in the sense of a reorganization under the bankruptcy laws like Chapter 11 in the US. The German website uses the same word, 'Restrukturierung', which has no connotation whatsoever that would indicate that the company is closing down. That would be 'Liquidation', 'Räumungsverkauf' or 'Geschäftsaufgabe'.
Wittner have said in previous newsletters that they will restructure what they list and sell, based on actual demand. Lots of Beaulieu accessories will probably get trashed or otherwise recycled because they no longer sell (even with discounts). So over the next 3 months (which includes the usual summer vacation period where many German 'Mittelstand' companies close down completely), they will restructure their warehouse, discard many product ranges, and overhaul their online shop and depository stock.
S8 film stock is unlikely to disappear. It will concern mostly camera-related hardware that is past its sell-by date.