I think this could be the reason. You have not mentioned a real source:
One of the link mentioned there takes to this thread but nothing similar there:
https://bitcointalk.org/index.php?topic=450381.0
COPIED:
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7. You said 20% interest per year, do I have to wait 1 year to get the PoS interest?
No. PoS blocks will be generated after you hold some coins in your wallet for certain period of time. For MintCoin the minimum requirement is 20 days. If you move around the coins (for example send to other wallet and then send back), the time will reset for those moved.
8. The PoS generated coins, are they eligible for new PoS block generations?
Yes. After maturity (50 confirmations), the coins will move from "Stake" to "Balance". Once the PoS generated coins in "balance", they will be the same as all other coins, and are eligible for future PoS generations.
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FROM:
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7. You said 10% interest per year, do I have to wait 1 year to get the PoS interest?
No. PoS blocks will be generated after you hold some coins in your wallet for certain period of time. For bankcoin the minimum requirement is 1 days. If you move around the coins (for example send to other wallet and then send back), the time will reset for those moved.
8. The PoS generated coins, are they eligible for new PoS block generations?
Yes. After maturity (50 confirmations), the coins will move from "Stake" to "Balance". Once the PoS generated coins in "balance", they will be the same as all other coins, and are eligible for future PoS generations.
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