Certainly:
This is incorrect. It will depend entirely on the circumstances and the honest belief of the accused.
This is explained in the Section 76 of the Criminal Justice and Immigration Act 2008, which was amended in 2013.
An Act to make further provision about criminal justice (including provision about the police) and dealing with offenders and defaulters; to make further provision about the management of offenders; to amend the criminal law; to make further provision for combatting crime and disorder; to make...
www.legislation.gov.uk
The use of disproportionate force can be regarded as reasonable in the circumstances, as the accused believed them to be. the scope is defined in subsection 2.
This is mostly guidance that I think your AI cobbled together from a solicitors blog page and a "legal guide for care givers". though the guide clearly states it is not offering legal advice. It isn't actually written the way you presented it. Some of the opinion is factually incorrect (shown in red).
I'd already provided you with the CPS guidelines which are included in your House of Commons briefing. Almost all of the briefing is focused on the use of force for self defence against a home intruder. There is only a small (and relevant) section that you have not quoted. The section titled
Use of Force against Those Committing Crime.
The common law right of Self Defence against a personal attack is different from the Statutory right in the Criminal Law Act 1967. Hence when you post about reasonable force as it relates to self defence you are referring to the "wrong law".
Imagine two Scenarios:
A threatens B with physical assault and leads B to believe his at risk of imminent unlawful physical violence. Under well established common law, B may strike first, there is no longer a duty to retreat first. (since 1967). Once A is no longer a threat to B, B has no further justification for force. So if A decided to run away B cannot chase after him to inflict further "self defence".
A is committing an indictable offence as part of a group, B decided to exercise his power under S3(1) Criminal Law Act 1967, he may use reasonable force to prevent the crime and apprehend A. His right goes beyond common law (see sec 2). B grabs a scaffold pole to assist as he is both outnumbered and suspects B is armed. A decides to run away, B pursues and may continue to use reasonable force as he believes is necessary to apprehend A, even if that force turns out to be disproportionate with the benefit of hind sight. see Section 76 of the Criminal Justice and Immigration Act 2008 above for details.
hence - self defence - wrong law.