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I've been told that pending transactions need to be kept in memory, so if they were kept going indefinitely, there would be a huge problem about memory usage. By closing the pay-out period after 7 days, that data is complete and can be purged from memory.

This would make the most sense but then isn't that just another issue? Scaling issue to be precise?

I suppose so, but since I'm not a programmer, I have no idea about what can or cannot be done.

I always appreciate an I don't know my friend... It usually means Im asking the right questions :-)