Technically correct only if you accept "vague set of traditions" as a valid definition for "constitution". This both contradicts common usage and enables tyranny, so I recommend rejecting it.
Where can I find the official list of which acts are part of the constitution? And what additional obstacles exist to changing those acts beyond the obstacles to changing non-constitutional acts of parliament? In common usage, a constitution is something that restricts changes to ordinary law. If a "constitution" is made entirely from ordinary law it cannot function as a constitution.
Before you demand more explanation on the spot, you know there's a Wikipedia page for that. It explains the components how they are legitimated and the mechanisms of the UK government that rely on it.