Levemir doesn't have a 24hr life- it's best work is done over 12-14 hours and most people on it end up splitting their dose. For example, I take 16 in the morning and 14 in the evening (12-14hrs later). Splitting the dose might work for your friend - something to discuss with their DSN/consultant.
My BG during the time 4h after my lunch and before dinner is always deadly stable - confirmed by dex and bg tests.
I say 20h because during the last 4h before next basal injection its my dinner time, so I always have some qa active. But my dinner ratio is the same as during the rest of the day and I never saw any unexplained rises during that time, so I wouldn't be surprised if my levemir wad still active during this time.
What I'm trying to say is that everyone is different and some may be getting 12h from levemir and some 24h. I wouldn't be so strict to say that everyone need 2 injections per day.
Of course not everyone using Levemir would require a split dose, but it's easier to get a true gauge what your BI is doing if you've checked it while fasting/carb free.
So my friend is T1 too and on injections she is on 30U of levemir basically she injects it at night but doesn't eat breakfast but still injects 4U of rapid in the morning to avoid going high....now this would mean her background isn't right? correct?
Maybe it goes back to the dawn of time when we used to actually hunt for our food...?
Imagine a prehistoric "non D" crawling out of the cave just after waking up.. Of course the beta cells are working fine, but there might still be a little liver dump to give a boost & carry the hunter to its prey... Which could be midday by the time captain caveman has stalked & beaten down Bambi with his mates...?!