Those are very valid questions.
Such a delay in the tabling of the departmental results reports is unusual. To my knowledge, they have not yet been tabled, even though the fiscal year ended on March 31. By April 1, departments should have already prepared a good draft, with missing numbers, of course, since the year is not over. One would expect these reports to be released a few months after the end of the fiscal year, allowing time for translation and quality assurance measures.
But you don't have these reports; no one does. This deprives you of information that could be important. If, for example, a department is asking for a lot more money each year, but is not meeting its own result targets, you would be entitled to rigorously question the officials and ministers involved about why they are asking for more money when they are failing repeatedly. This deprives you of critical information about departmental results when the government is asking you to approve funding for these entities. So there is a glaring information asymmetry.
The government has the information and has access to it, of course. As parliamentarians, you don't have that access, but you are the ones who have to approve the funding. There is a significant information imbalance.
As for legislating a deadline for releasing departmental reports, I would say that is a great idea. It would prevent departments from stretching the rubber band, every year, for the release of this information. There's nothing like a firm deadline to get people to work.