You assume correctly - the shoulder straps are fixed in place; the only adjustment is by lengthening or shortening them (normally, on your chest) - there is no way to move the attachment point. If you're lucky, and it fits (and I am), that's fine. Otherwise, take a look at the Nimbus Ozone or one of the other packs that do have the adjustable suspension. (It's virtually the same packbag, plus or minus a few hundred cubic inches.) Non-adjustable reduces the weight as much as possible. It may be a no-no (though Gossamer Gear might join Granite Gear to dispute that), but it works for me.