I read your question differently than the responses above...I think you're asking about whether status points are deposited in batches or carefully, one by one for status change purposes?

In my experience there is nothing guaranteed with CX tech. But more likely than not, your flights if close/same day will post their relevant status points a few days later at the same time, and your status will be upgraded based on all of it at the end of whatever day it posts. That is to say, you will most likely NOT get the result you want: to be bumped up a tier level due to the first flight, and then the miles from the second flight will accrue to the next earning tier.

Instead, my bet is you will get all miles/status points deposited simultaneously, and then bumped up to the higher tier at the end of whatever day it is they post together, so you will "lose" some status points earnings potential.

Maybe you can strip your MPC# off your second flight while transiting. Not sure if they'll let you do that or if feasible but others here probably know. So you have your number on the first flight, and strip from the second, and claim back the second flight after you get your status upgrade. You might not like not having status on board that flight but I think it's the only way I can think of to guarantee the outcome you want.