There was definitely a change made.

Current Base Food Production in my main food city: 393700

Mayor is 521 politics - prior to change his bonus to prod was 2051177 (521%)

Now he only adds 1574800 (400%)

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Updated:

When I swapped his armor to intel and let the system update it stayed at 400% still, then when swap it back to politics it changed to the correct amount.

Not sure why it was exactly 400% though prior to me messing w/the armor.

Something is bugged for sure.