Microsoft Defender For Emails & Collaboration

Hello All, 

Based on my organization's requirements, we have configured the Microsoft Defender For Emails & Collaboration Threat policies. 

But, Under the Preset Security policies., we haven't enabled Standard or strict protection policies. 

What will happen if I enable the Standard or strict protection policies now? Will it revert/break all custom policies created based on the organization's requirements? 

Any suggestions? 

Thanks,