Well, that is a pity; I rather liked that stuff.
Still, I quite understand that it may not be economical to keep two product lines that serve basically the same purpose and effectively compete with each other. Keeping Ilford as a whole profitable is more important than any one product line.
I don't see how the ULF thing would help. The issue is not that particular sizes sell in small quantities, but that the emulsion itself sells in small quantities. The huge quantity of HP5 and FP4 sold allow for annual batches of weird sizes to be cut from the same stock; the preorder process just ensures no wastage from unsold/unsaleable packs in bizarre sizes.