I have an alternate perspective to consider. It sounds like the recent tasks you've been doing are content related, not client strategy which seems to be what you want to do.

Is it possible that your employer has heard your complaints about detailing different blog articles for a year out and decided to create a position that does that type of thing so client managers can focus on client branding strategy? I don't work in your field so it's possible that I'm interpreting certain job functions in a different way. It sounds like a content manager would come up with content for blog articles.

I thought I remember you mentioning you wanted to do what they hired you to do and most of what they asked was menial tasks that related to content. I know you said you don't have any real information on the role of content manager. I'm wondering though what reason you would have to follow the tasks you don't like into a new role that hasn't been fully developed. I would think you would be glad to see content related tasks leave the job you were hired to do, but that's just my outside limited perspective.

Good luck in your review next week. Hope it goes well.