You asked my opinion in regard to the timings i gave. Those were just monitoring times I use to see how I react to protein, and I often find my bgl is higher at 4 hrs than at 2 hrs with some meat or fat heavy meals (stews, curries etc). As I am not an insulin user myself I cannot possibly advise on medication, but I have seen others discussing the points I raised on this forum regarding split bolus and pizza effect delays.
Reading some NHS literature, then they seem to only allow for carbs, and do not consider split doses. I have seen split doses being recommended for pumped users where the adjustment is a relatively simple dial up option.
This may be of use
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6375528/
And something about pizzas
https://diatribe.org/pizza-and-blood-sugar-control-not-quite-easy-pie
And finally, one on protein counting for insulin
https://www.diabetes.co.uk/nutrition/protein-and-diabetes.html
Note: this article has an error in it. ketones are esters of fat and are produced from fat when it is broken down during metabolism. ketones are not proteins, Proteinuria is associated with kidney damage not protein intake and ketones are not any indicators of AKI (which is the what the microalbimuria marker shows) However, there may be an association between kidney damage being triggered by very high protein intake. This may be relevant to discuss further in the Carnivore thread??????
But none of these articles above is NHS approved, so treat with caution.