Hi Sternberg76 et al! I too posted an authenticity request, I believe it was post 8008 (I think). Like your purse, the sleeves of my sweater do not match the body in terms of the check placement. (However, I'm new so not sure if I will get an answer lol.)
Anyways, I'm no Burberry pro, but I found this eBay guide on Burberry purses and the kind lady who wrote the guide shows purses very similar to yours in the same pattern and style.
Under the paragraph, "Pattern Alignment", this eBay seller states that: "The pattern in both the Nova Check and Classic Check must match as pictured below. The pink/red line and the black stripes must meet on the side and on the bottom like you see in these pictures. Sometimes, you will come across authentic Burberry with pattern that do not match too well but those are fairly rare."
Check it out:
http://www.ebay.com/gds/Authentic-BURBERRY-purse-buying-guide-/10000000000799495/g.html
Hope this helps you!