That... Uhm... That sounds to me like a perfect situation to balance stuff, specifically for the reviewers to make the game as enjoyable as possible and then when it releases for people to buy, boom, grinding time.
Wouldn't even be the first time a game changes after the reviews get released, people mostly noticed that because patches changed them, but here, we would never notice because it's a whole separate build, they could do stuff in a situation like this that I probably can't even imagine, holy shit. This just smells incredibly fishy to me.
Reviewers should decline this shit, smell that this is fishy all by themselves and decide to test the retail version and meta websites shouldn't allow reviews out of this fishy situation.