Policy is to address a specific issue, a plan are the actions/steps to achieve an objective.
Let’s take the renters rights bill you mentioned, what is the point of the bill? To improve renters rights, ok so why is that a good thing? Because it’s the right thing to do to help those whose housing situation is vunerable. Ok great, its seems like a good thing to me but it’s a policy to support an ideology (other ideologies on renters are available).
You could say that Reeves’s “fiscal rules” on the economy are a plan. What’s missing is the coherent steps to get to that goal, and, believe it or not, this government is more interest in social issues than businesses which doesn’t usually lend itself well to a coherent economic policy.
The way I read your second paragraph said the budget problems that Reeves faces are all down to the Tories, you stated it as fact (which is wrong) but in your first sentence you’d complained about political commentators stating things as fact when they don’t actually know. I may have misread what you meant of course.