Some users have recently had their accounts hijacked. It seems that the now defunct EVGA forums might have compromised your password there and seems many are using the same PW here. We would suggest you UPDATE YOUR PASSWORD and TURN ON 2FA for your account here to further secure it. None of the compromised accounts had 2FA turned on.
Once you have enabled 2FA, your account will be updated soon to show a badge, letting other members know that you use 2FA to protect your account. This should be beneficial for everyone that uses FSFT.
Confirm if these were indeed DC HC520's? Understand those were the XBOX black and not the Easystore...
Amazon down to $199 - down ~$15 on 12TB Easystore
Seems I am about 3 months late as the 6.4 are now listed for $800 +. Still need to do more reading to understand how well they are supported in Linux(Debian Buster).