Roku menu path Settings > System > About will show you the model number of any Roku. Per the Roku 12.0 Release Notes, Roku 4400 will not receive this Roku update.
Roku is gradually rolling out an update of its operating software from version 11.5 to 12.0, and this may be the update you received. The rollout is done individual Roku installation by individual Roku installation, with an update schedule known only to Roku. If you have multiple Rokus, they may not become eligible for the update at the same time, even if they are the same Roku model.
Roku menu path Settings > System > System update will show you your current Roku version number. Down in the lower left corner of this screen it will also show you when your last update was installed.
A new release sometimes creates problems that must be addressed. If you are having a new problem with your Roku, does its beginning coincide with your installation date?
In past major Roku updates, I've found that updating the Roku software may not automatically update all channel apps that have new versions to accommodate the Roku update. I don't know if this is the case with the 12.0 update. Manually running an additional update check as soon as you receive the Roku update can make sure you have the latest versions of all your channel apps and prevent many update-related problems (Settings > System > System update > Check now).
Despite having had access to the Roku update as it was being developed, some channels may take a while for their developers to issue needed updates, so a manual update check as above to catch any more recent updates is always a good first step when running into specific channel problems.
Roku Community Streaming Expert
I am not a Roku employee, only a user like you. Please, no support questions via private message -- post them publicly to the Community where others may benefit as well.
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Ultra 4800 | Streaming Stick 4K+ 3821 | TCL Roku TV 43S245/C107X
