So far, from what I can tell you, Premium members just took over the previous VIP members. All the features are the same. It frees up the VIP members group for something else, and that is left for Alex to decide.
As for people who donated before the subscription option, I'm not sure and would like to know myself if there is an expiration term.
For users who donate through the subscription method, the term is outlined when you pay through your usercp and automated for the most part. You will get approved and added rather than Alex manually having to put you in.
I think I remember what you mean about some VIP's being Premiums, and others weren't, I was online. Maybe Alex was testing the waters before throwing everyone in.
Everyone who was previously a VIP should be a premium now to my knowledge.
If someone isn't there please notify Alex directly so he can take care of it.
I just looked through the subscription method, and it seems it doesn't tell me what my expiry date is. I wonder, does my premium member is permanent or what?