Uncaught Error: Cannot enable prod mode after platform setup #3893

After updating to 4.5.1 and doing a ng build I am now getting the following error when I try to visit our site. Does anyone have any ideas?

Uncaught Error: Cannot enable prod mode after platform setup. at ce (vendor.de69c82deb44e6b6e7ea.bundle.js:1) at Object.cDNt (main.f5488ece5fd3a5a2f463.bundle.js:1) at n (inline.81d87e40e2b3ec0c3391.bundle.js:1) at Object.0 (main.f5488ece5fd3a5a2f463.bundle.js:1) at n (inline.81d87e40e2b3ec0c3391.bundle.js:1) at window.webpackJsonp (inline.81d87e40e2b3ec0c3391.bundle.js:1) at main.f5488ece5fd3a5a2f463.bundle.js:1