don't understand what you mean by provenance.
according to the then PR language, helmut lang jeans as "casual line" while helmut lang was as "luxury and comfort".
actually some of the stuff was like a casual version of a match from the main line, in terms of fabrics and constructions.
this is what was written on the ads.
"khakis, chinos, denims, workwear, casualwear, functionals, protectivewear"
I think the actual situation was that they conformed to onward's usual strategy. a second line or lower priced line was (maybe is) one of what you'd start eventually when you become onward's partner.
2000 S/S might have been the last season.
for 2000 F/W pieces, the tag/label was no longer helmut lang jeans for sure although the jeans line continued to be available.