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Black Friday not the cheapest time to shop, says consumer group
(www.theguardian.com)
This is a most excellent place for technology news and articles.
Wouldn't it be noticeable because this new "-a" model would have no ratings/reviews?
This practice is most common with in-store "doorbuster" type deals.
Generally an observant person will notice this, especially if they actually read the box. The model number extensions will vary though, some are 6 characters for example.