Your engine is pretty new. Notice that the sodium came down on the second uoa also.
I don't think sodium is a component of oil ageing.
I expect it will decline further as the engine runs in more. I think you will see a trend downwards.
Haley, could be. Well I should have my GC 0w30 coming up soon and it will have 5K on it with about 6-7months on the oil. Some say it may be a coolant leak, but I haven't seen any drop in coolant.
Do you do a lot of driving near the ocean? I've heard that you can pick up a lot of sodium through your air filter from salt dust. Since your second UOA has relatively high silicon, this is feasible.