The reverse factories can duplicate some of the mixed metals from Bob's Metals, Chemicals, and Intermediates. I noticed this first with bronze, but it may also be true for other metals.

Example: https://youtu.be/372RkLTh56k
Blueprint(Requires: Reverse Factory, Bob's Metals, Bob's Flexible Inserters, Bob's Power):
0eNqdk+1ugyAUhu/l/AYjqPXjVpqlQXrakCkYwKWu8d6HurRLJNvSfyLwPC9vcu7QdiMOVmkPzR2UNNpBc7yDU1ctuuWfnwaEBpTHHgho0S8rZzph6SA0djR8XZFmMBNQ+ow3aNj8RgC1V17hhlsX00mPfYs2HPgVRGAwLtw1evEHXp4UBCZo6CEp5pnscPxFHI/jsgcOO5TeKkl7dVP6Si+j1ULiHkm/iSyUYFGqtbLWGv2JVHSdmSDiyZ+xx9Z5sfBoHoGzPwIXT5AX8p0q7dD6sLNHZSsoDTHPKgTdtkKQszXDaefdrGnC6pqzqozKD6+Vz+JPKf//lHzjzPHwW/Y04WnGeFRVPVQWP9A6pBchvbETZREbX3k8Bqpfa6BYGgiDsk5W82MQCSxx1guHquS8YnVaBvMX4JcyZw==

So the only way that could be happening, is if there is a recipe in the game defined as "bronze-plate", which is unlikely, because most of the recipes Bob has are called something like "bronze-metal-mixing-copper" or something more descriptive, since he usually has multiple ways to create the same alloy.

At least, I'm preeetty sure that's what happened. The only other explanation is that something breaks in the logic of the reverse recipe, but only with bronze plate (which would be even more unlikely)

I'll have to take a closer look to know for sure, shouldn't take long as I have a long weekend off.

I figured out the issue. Bob coded some of his item results oddly. So the function I have that sets the ingredient count for reverse recipe defaults to 1 (because a recipe that produces only one of an item doesn't define that number), which is wrong in this case.

The way he does it isn't "wrong", per se, just unusual. So I'll have to fix it from my end.

EDIT: Should be fixed as of v5.1.6

Thank you for the quick response.