Without knowing exactly what level of detail of transparency you're asking for, I would point out that changing the components of and additions to blends to deal with the vagaries of a commodity crop and it's markets to get to a reasonably similar result year over year is the better part of the blender's art.Something tells me this is about to become a big differentiating point with blenders.
I really hope that the others are at least transparent about it.. Like if Boswell wants to keep Northwoods but their latakia source changed (random example) at least mention it in the description going forward, if not appending it... "Northwoods v2"
Introducing a blend that's 70% this and 30% that to great reviews doesn't mean much of the "this" available next year - tho of exactly the same grade - comes from a different region, or went through a drier summer, or has 1% less natural sugars in it, etc.