I had long believed that the Roman Empire exerted full control over Egypt from the time of Augustus until the late Empire, possibly extending as far as the Vandal invasion in the fifth century.
The informative article below discusses Egypt during the Roman era and explains that Egypt ceased to be the "breadbasket of Rome" after a revolt led by the Egyptian priest Isidorus in AD 172-173. The unsuccessful revolt, known as the Bucolic revolt, resulted from tax issues and cultural resistance against the Romans and had a lasting detrimental impact on the Egyptian economy.
https://the-past.com/feature/palmyra-blemmyes-diocletian-and-egypt/
See Cassius Dio “Roman History” Book LXXII
https://penelope.uchicago.edu/Thayer/E/Roman/Texts/Cassius_Dio/72*.html
https://en.m.wikipedia.org/wiki/Isidorus#:~:text=According to the Roman historian,marshes of the Nile Delta.
It appears that after the revolt, the gain supply to Rome resumed. This new supply, however, seems to have been neither as reliable or plentiful. Unforfortunately, there appears to be very little written on the revolt and its effect on the Egyptian economy.