Hi Robbie

If a user last connected to you when you were an ultrapeer, then shut down for a week or so, they would attempt to connect to you when they started up again.

You might even see someone attempt to connect months later, if that was the last time they ran LW.

Failed connection attempts remove invalid IP's (or they are supposed to with decent clients), which would explain why you don't see repetitive connection attempts from the same IP.