There is an exception when it comes to merit sources. Theymos allocates each merit sources certain amount of sMerits every momth, for them to distribute throughout the month. Now if I understand correctly, if left unused, the sMerits will get a reset after the month is over. But we aren't talking about that here.
Merit sources have two types of sendable merits. The usual sMerits like everyone else, generated when someone merits your post, and source merits that go in a separate pool. They first have to spend all of their source merits to begin spending sMerits. If they never manage to do that because of big source merit allocations, merit sources will have a big amount of sMerits in their accounts that keeps growing but doesn't get spent or rarely gets spent.
Well this is news to me. I mean I knew there were 2 types of sMerits when it comes to merit sources, but the way they worked was totally unknown to me. The fact about, merit sources spending their allocated sMerits before they could spend the earned sMerit, I wasn't aware of it. I'm curious about how does the whole interface looks like, I mean like does it says, "You have X amount of allocated source sMerits, and Y amount of earned sMerit remain"? Also, how much a merit source typically gets? (referring to a range like 100-500-1000, not any specific amount).