Although I cannot release specific information about the carriers’ approval processes and status, I can tell you that the tests performed both on Fairphone’s and partners’ side are thorough and cover a multitude of different areas (from customization to telephony features).
Sometimes, especially during OS letter upgrades, issues can be found during these testing sessions and it is not always so easy to solve them. Generally speaking, when Fairphone makes the decision not to release a specific software to a portion of customers, it is because the software can negatively impact the usability of the device, one way or another.
And that would make receiving the software update pointless, as the users affected would encounter a degraded experience.
We are working hard to align the user experience on Android 12 for all our users as soon as possible.