Thank you for the quick reply.
My rate of these messages for my miner is not very often, especially compared to some of the miners I've seen connected to my node. My reject rate is around 1% on average per the
p2pool node stats (Litecoin scrypt node), but I was not sure if their was something else I could do to reduce the rate. I think I run a pretty decent p2pool config, but I am always looking to learn and improve.