If you go into your Distribution Manager it will tell you generally when Smashwords will "ship" an update to any given distributor. Once the store receives it expect a few more weeks before any change is updated.
Kobo is the slowest distributor to update pretty much anything on Smashwords. Last I checked they still had my old book cover that I updated last August even though all the others got the update within a month. They're also the last to update sales every month. I'd be annoyed at all this but for some reason Kobo is my 2nd best place for sales after Amazon, so
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