Postfix Fatal - Postfix Mail System Is Not Running

I'm running into an issue with my VE instance after needing to rebuild following a node facing a board failure.. Everything was going good up until configuring email alerting. When trying to reload postfix, I'm getting hit with the following:

postfix: Postfix is using backwards-compatible default settings
postfix: See http://www.postfix.org/COMPATIBILITY_README.html for details
postfix: To disable backwards compatibility use "postconf compatibility_level=3.6" and "postfix reload"...

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