Slate AX offered new firmware 4.4.5 but then it fails

Confirming same 4.4.5 upgrade alert on Beryl AX MT-3000, listed on download centre as stable release, and alerts as ‘not official released firmware’ on upgrade attempt.

A version jump from 4.2.3 to 4.4.5 as ‘stable’ is somewhat suspicious to me, as is release date of 11 August 2023 and notice 24 August 2023, but I do not have insider knowledge if this is a valid concern.

Can I please ask forum mods or firmware devs in the community to confirm if:

a) 4.4.5 firmware has a release signing issue that is known, will be resolved, and is safe for install,

or,

b) 4.4.5 firmware is of unknown or unconfirmed origin, and if so, the security risk and actions advised.

I just installed the 4.4.5 build from download centre, and it worked (with not official released firmware warning again).

I will now downgrade to 4.2.3 until authenticity and security is confirmed.

If this topic is in another post thread I have missed, please feel free to link. Thank you @mfld for your original post.