FBA Sub Same-Day Delivery - how do I know if my items are enrolled?

Reading this help page, the link to see which ASINs are enrolled just takes me to the manage FBA inventory page. I don’t see a way to filter my FBA items by SSD enrolled/eligible. Does this simply mean I have no enrolled items?

I also saw this from ecommercebytes about maybe being able to pay to get items into the program. Don’t love the idea, but for some items it could be worth it. I didn’t receive this invitation, has anyone tried this? Did it boost sales?

Like all things ecommercebytes now, the link is broken, but these two articles might cover it: