But do sourced merit actually do expire?? Only do see such statement but have not seen any post of merit source talking about their monthly sourced merit expiring instead I do see the ones who parade up to 4k+ Smerit.
I don't know how to explain this to you - if you're given 10 and manage to exhaust only 5, you get only 10 again the next month, the other 5 doesn't roll over.
Well I get your point now, so that is for example when a total of 100 merits are being allocated to source and they spend only 80 remaining 20 left, when toping up to you again instead of having 120 as total allocation you would now be topped just 100 and the previous left 20 wouldn't count anymore, or we can say they will automatically top 80 back to the remaining 20 to make it back 100.
In summary, what you spend that is what they top back the next month, So it doesn't expires rather they top back what you spent added to the left over to give you back the exact allocation.