Level 21
Microsoft Security Essentials (MSE) will continue to receive definition updates for new malware after Windows 7 reaches End of Support, even though a Microsoft support bulletin states otherwise.
In Microsoft's FAQ about Extended Security Updates for Windows 7 it states that after Windows 7 reaches EoS, MSE will no longer protect a Windows 7 computer.
Will Microsoft Security Essentials (MSE) continue to protect my computer after the end of support.

No, your Windows 7 computer is not protected by MSE after January 14, 2020. MSE is unique to Windows 7 and follows the same lifecycle dates for support. Learn more about MSE.
This was concerning for those users who continue to use MSE on Windows 7 as it meant they would have to get a new antivirus software to stay protected.

In a Microsoft AMA about Windows 7 hosted on the Microsoft Community Forums yesterday, Woody Leonhard asked if it was true that MSE would no longer receive malware signatures after the January 14th, 2020, EoS date.
Microsoft Employee Mike Cure said that MSE would still get signature updates after January 14th, but shared information from a Windows 7 End of Support FAQ that explains that the Microsoft Security Essentials program will no longer receive updates.
Microsoft post in AMA
Microsoft post in AMA
While this is surely good news for MSE users on Windows 7, it still does not mean you should continue to use Windows 7 or Microsoft Security Essentials for that matter.

Without a subscription to Windows 7 extended security updates, using the unsupported operating system will open users to vulnerabilities that will no longer be fixed. Furthermore, it is not uncommon for vulnerabilities or bypass methods to be discovered in antivirus software.

Therefore, even if you are willing to risk being affected by new vulnerabilities in Windows 7, it is still possible that malware distributors will come up with methods that bypass detections in Microsoft Security Essentials.