I'm seeing some URLs on our site are generating two directions. One of the redirects is caused by nop not bothering to include the language in the redirected URL.
Somehow I got a Category called "corkscrews" (Standard), "cutlery-accessories" (English) and some french string for French. A incoming URL of /en/corkscrews will get redirected (302) to /cutlery-accessories. Since that doesn't have the language on it, nop will then redirect to /en/cutlery-accessories (a 301 this time).
Redirecting a single url twice is bad. It would appear that the issue is that the first time it redirects, it should include the language in the redirected url.