What's my best bet for firm choice?

My full situation:
I am not eligible for contextual offers. I was diagnosed with ADHD a few weeks ago (after all my offers came back so did not effect my application). I am currently studying Geology, Biology and Maths (with mock grades A, B+, D+ so have just gotten a maths tutor). My predicted grades were A*AA. In order of offer received, I got 5 offers studying geology/earth sciences:
Keele - ABC or BBB
Birmingham - ABB
Bristol - ABB
Southampton - BBB
Edinburgh - BBB
My favourite uni was Bristol, with Southampton in second. Keele looked okay at pinch. What's my best bet for firm (am just assuming Keele is best for insurance)?

I would say Bristol as firm and either Keele or Southampton as insurance.
Ideally, you would want your insurance offer to be lower than your firm, so that if you don't get the grades for your firm, you may still get them for your insurance. I would pick Southampton as insurance if I were in your shoes since it's your second fav. However, if the flexibility of the Keele offer is something you prefer (especially if you are worried about maths), then go for it. Beware that some unis might still maintain their offer even if you miss it (especially if you only miss it slightly). I don't know if that applies to Southampton, though.

As for the Bristol choice as firm, in my opinion you should just go for what's your fav. At the end of the day, the moment you meet your firm offer, all of your other offers are null. You want to be sure that it's your most preferred option, otherwise you might end up in a situation where you have the grades needed, but are stuck with a less preferred uni. If you don't meet the firm offer, that's what insurance offers are for.

Its still worth telling your F & I Unis about a late ADHD diagnosis - this might make a difference in August if you just miss your grades.

Thank you for your insight! Great point for Bristol as firm, and the keele-southampton part is a good shout (I might put off responding to offers as much as possible to see how my maths goes haha). Really useful advice, have a superb day!