I think you may be overthinking this, or at least really majoring in the minor here. A few things:
Those limits are based on rate equations, aka X amount of substrate per minute. Unless you define time then we cannot even begin to discuss upper amounts. If time is set at 24 hours, you are no where near the limits of uptake.
Have you tried eating more and seeing how it affects your body?
Yes, overthinking it IMO. I am utterly confused as to why you are wondering if you are near limitations on nutrient uptake on protein, then you decide to only have 2 meals a day since 'assimilation takes 6-8 hours'?
Honest question, have you any prior research experience done on the intestines and stomach or are you just rehashing what other people have said and are working the numbers in an illogical fashion?