I have commented before, on another thread.
My current status, on my medical records is "Diabetes Resolved", and I still receive invitations (which I accept) for retinopathy screening, so I think there's definitely some variance in how Practices choose to administer things.
I'll continue to accept invitations I receive. My optician uses some nifty photographic equipment when I have my routine sight tests done, but I'm hopeful the diabetic screening service have a more in depth experience of interpreting the images.