Ah, my bad, I read september 7 2015 instead of 2016.
If you have a valid sub, you don't need me, you can upgrade directly from your dashboard.
If you go to "My purchases", you'll see your recently purchased sh404SEF subscription and 2 large buttons below: one is for renewal with a discount and the other is to ugrade to another plan, which is just what you want to do.
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