Parent might have given wrong tax details, maintenance loan is more than I expected

Just got my letter from student finance telling me how much maintenance loan I will be getting for next year but it is approx £900 more than I thought I would be getting.



Using the save the student guide where it tells you how much you can expect for each band of household income, I should be getting the minimum amount of just over £4000 but in my SFE letter its says I'm getting approx £5000 which according to the save the student guide, I would only get if the household income is around £55,000. Which just so happens to be the amount my parent earns from their full time job but doesn't include the extra money from the self employed work which brings the total household income past £70,000.



So I'm wondering if my parents made a mistake when filling out their financial information, but not sure why student finance would accept the application without checking the details are correct with HMRC first. Also we have no way of checking what financial information my parent gave now that the application has been accepted.

The information for this academic year will be based on the 2019/20 tax year; were they earning the same amount then?