Since it is just the sleeves, I don't think it would be that much of an issue. Even if you can still get the same dye lot, there still might be variation compared to the same one you already have based on how the yarn was stored, etc. If you had run out say on a front and started with a new dye lot halfway up, it might be obvious, but with the sleeves I wouldn't be that concerned. Or at least until I saw the new dye lot yarn.
