MN 72 appears to say "na upapajjati" does not apply to the Arahant:
MN 120 appears to say: "na upapajjati" does apply to the Arahant:That’s why the Realized One is freed with the ending, fading away, cessation, giving up, and letting go of all conceivings, all worries, and all ego, possessiveness, or underlying tendency to conceit, I say.
Tasmā tathāgato sabbamaññitānaṃ sabbamathitānaṃ sabbaahaṅkāramamaṅkāramānānusayānaṃ khayā virāgā nirodhā cāgā paṭinissaggā anupādā vimuttoti vadāmī”ti.
“But Master Gotama, when a mendicant’s mind is freed like this, where are they reborn?”
“Evaṃ vimuttacitto pana, bho gotama, bhikkhu kuhiṃ upapajjatī”ti?
“‘They’re reborn’ doesn’t apply, Vaccha.”
“Upapajjatīti kho, vaccha, na upeti”.
“Well then, are they not reborn?”
“Tena hi, bho gotama, na upapajjatī”ti?
“‘They’re not reborn’ doesn’t apply, Vaccha.”
“Na upapajjatiti kho, vaccha, na upeti”.
How is a contradiction avoided here?They realize the undefiled freedom of heart and freedom by wisdom in this very life. And they live having realized it with their own insight due to the ending of defilements.
So āsavānaṃ khayā anāsavaṃ cetovimuttiṃ paññāvimuttiṃ diṭṭheva dhamme sayaṃ abhiññā sacchikatvā upasampajja viharati.
And, mendicants, that mendicant is not reborn anywhere.
Ayaṃ, bhikkhave, bhikkhu na katthaci upapajjatī ti.