Is it possible to upgrade the TX Ultimate switches to be Matter compatible out-of-the box?
Is it possible to achieve such a feat through just firmware updares without the need of developing new hardware?
No, the TX Ultimate cannot be “upgraded to Matter” via firmware. The device lacks the required factory‑installed Device Attestation Certificate (DAC), secure key storage, and CSA‑compliant provisioning. These elements must be added during manufacturing, not through software updates.
While the ESP32 chip inside technically supports Matter over Wi‑Fi, the TX Ultimate wasn’t designed with the necessary security hardware, memory layout, or certification path. Sonoff also doesn’t provide Matter upgrades for existing models. They release separate Matter versions (e.g., Mini‑R4M, M5 Matter).