Support for Indie Authors discussion

I published my book in two formats through KDP, (eBook & Paperback). When publishing I selected book categories, (maximum of two allowed), and made them the same for both formats. Now I am considering changing the categories to see if it helps readers find my book.

I have two questions as follows:

1) Should both book formats list the same two categories? Or, is there a benefit in making them different as both formats are linked? I understand selecting different keywords for each format has an advantage in that it yields 14 keywords as opposed to 7. Therefore, I am wondering if the same is true with categories, (i.e. 4 is better than 2)?

2) If I change categories, will I loose my Amazon ranking, (which I understand is based on sales / keywords / book description / category selections / etc.)? And, if I make the change and don't like the results and then change it back--will I loose my previous ranking, or will it revert back to what I had?

Help with this question is greatly appreciated, Thanks !

They are linked, so keep them the same, but it is worth experimenting with categories, taking it down to a category that is getting traffic with less than 10K titles. (that comes for three different professional marketers and I have a tendency to believe them.) It will take you some time to find those categories. You can also contact Amazon support to get it into up to 8 categories but you need to make sure you have the full link ie sci-fi-dystopian-mermaid-roamce (probably no such category but sounded good...lol) You may have as high as six to eight words for the category if you can find books like yours and niche them down. The thing about categories is that if you get in a smaller category, you are more likely to make more sales and rise in the ranks. That is one thing you can change without a problem. As to if your ranking will come back. probably not unless you make more sales.