I have the Blaze and do not have the issue you are having. How long is your torso from neck to waist? Measure that then compare to GC recommendation. If it within range, there might be adjustment to frame sheet to be made? perhaps moving shoulder strap down a notch? It sounds like the backpack is too short for you.
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It is one of the blessings of wilderness life that it shows us how few things we need in order to be perfectly happy.-- Horace Kephart