Can you appeal to student finance in-order to get more maintenance loan .

I’ve been supporting myself since after GCSEs. Just finished my Alevels and I was supporting myself all the way through right from meals, school resources, transport(my college was 2hours away so it was around 90ish a month), medications,everything. I even have my own fridge in the garage. Basically the only thing they have been providing is a place to stay. FYI I was working 12-36hours a week up until may before exams I obviously had to miss some lessons, so it was had to keep up with everything, I had zero social life because I was either studying, sleeping or working, nothing in between and I don’t wanna be in that situation again while at uni though I expect to work but not too much as it’s a full time course.

I haven’t applied for a student loan yet because am taking a gap year to save up some but I did some calculations and it turns out I will get approx 5000-6000 maintenance outside London. I totally not expecting even a £1 from my parents when I leave for uni because that never happened even when I had barely any transport to college and end up getting a credit card.

Btw I am 21, well I will 21 at the start of sept 2020, am I even a mature student? Though I had been in Education leading up to that time.
And also while calculating how much I was getting,(don’t remember which section and neither how it was stated) but I think it was something like “ household income plus yours if you 21+) I only put my parents because I am not expecting to work fulltime as am studying fultime
And I can’t apply for estranged/independent student because they require you not to have been in contact with your parents for a certain amount of time.

So lets say I apply, and get 5000ish , can I appeal for something more.