FWIW :
I had contacted Peter Steinberg (peter@gosgc.com) back in May who says he is Director of Operations at SGC regarding :
Pop Reports
Registry
Cert Verification
I also told him about the Net 54 forums and suggested that he might want to join as lots of his vintage customers are here.
I received the following response -
Thank you for taking the time to reach out. We greatly appreciate your longtime support!
Our volume is currently up 10x what it was only a few weeks ago and with the challenges of Covid19 factored in, things are very busy at the moment. This answer will be much more concise than I'd normally like it to be, but please forgive me due to the circumstances 
1 & 2. Pop is coming before Registry. Pop will be released within weeks at this point, not months. When the registry is fully built out, you will be able to register all of your SGC cards no matter when they were graded.
3. Cert lookup will be available on the website, but it will take a backseat for now due to improvements of higher priority. For now, you can contact Nick (the head of our Research Department) at nick@gosgc.com. He will be happy to verify certification codes for our collectors.
I won't be making an account on Net54, but I will be doing everything in my power to bring our collectors closer and closer to the team/operation that they entrust with their cards. Again, times are extremely busy now, but please rest assured we're signing a lease today on a new (larger) space, conducting countless interviews to hire more great people, and are working very long hours to ensure our collectors remain satisfied with the level of service they receive.
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