The DPI feature has stopped being tested, so even if you install the beta v4.8.99 firmware, the related functionality is no longer available.
At present, this firmware is only used for testing the Amnezia obfuscated VPN.
We plan to officially launch DPI feature in version v4.9, so please stay tuned.
This limitation is time-based (2025/12/28), so if the router has just been powered on and hasn't synchronized the time yet, it may be effective for a while.
And it will become inactive once the time synchronization is complete, as shown in your diagram.