I saw that the user LUCKMCFLY has 742 activity and had received 250 merits yesterday, but his profile shows as Full Member. From what I know is that once you have 250 merits and 240 activity, you'll be promoted to Sr.Member. But in this case, he is stuck as Full Member. Is this a bug or am I missing something?
He's Sr now. And he received those merits just recently, about 15 minutes before you took the screenshot, not yesterday (your screenshot shows the "Sent" part of his merit history instead of "Received"). A slight delay is normal.
Thanks suchmoon