Soooo... , I suggest you, @tiker, to blacklist the node of lcharles, as he is "ilegally" forging with my balance and confusing the network. And I ask you, @lcharles, to stop forging with my balance, as my leasing already finished on the longer fork of the blockchain. Otherwise I have to think that you asked me by PM a balance to forge with in order to just attacking the NAS network.
Chances are, lcharles' node is stuck at a block near mine. That's the only reason why lcharles' node would continue trying to forge blocks with your lease. That node hasn't reached a number where the lease ended. That could be why my node is trying to accept blocks forged by lcharles' node and why signature errors are appearing for blocks you forge with your account - my nodes think that you should not be forging with your balance yet and thinks it's still with lcharles.
I still don't understand why leasing your balance to someone else with an unstable node could cause this issue. In theory, it shouldn't.