Printing Color vs B&W on Kodak metallic paper-question

I recently had several copies of the same print done-some on regular paper, some on metallic paper.

The same picture in color showed a noticeable color banding around the bokeh in the background, whereas the black and white just had a gray blur. I was wondering if this was because the print company readjusted my settings (they weren't supposed to) or is it because the paper handles color and b&w prints differently somehow?

I love the way B&W shots look on the metallic paper and will be printing more for my personal use (framing for around the house). Any tips for optimizing my print in PP so that it looks it's best on that paper? Should it be extra contrasty or saturated, or less?

I think that the paper handles color a little differently than BW, but only from the standpoint that only certain color images seem to work well with it.

On the other hand, most BW seems to work with it. I tend to like the ones that have more contrast or appear more "edgy" (specific term I know ). I would say, that if you like the prints you have been getting, I wouldn't worry too much about changing your workflow much.