Worried about grades for apprenticeship offer

I recently got offers for 2 different apprenticeships. One of them is in finance for a transport company and the other is for an accountancy firm. After weighing out the two of them, I believe that the latter is the better of them.

However, the requirements for that one listed fall into A-C A level grades. I had the predicted grades to nail the interview, but I didn’t perform well on my actual A levels due to a lot of stuff I was dealing with at the time (and my grades for mock/practice tests prior that I performed similarly in were nowhere near good enough). I’m worried that when results day comes and I’m far below the grade boundary that the offer will be rejected.

The offer for the transport company isn’t reliant on the grades as it can be done off GCSEs alone. I’d likely be safer going for that one, but I don’t think it’s anywhere near as good. At the moment I haven’t had to sign anything and plan to drag both offers for as long as I can go without committing/signing but in the case it gets to that point, I want to know if there’s any likelihood of my chances for the apprenticeship to be jeopardised after results day where I don’t get the grades (and I can guarantee I haven’t got them).

I’m going to read the contract to see if it says anything about that as well as ring the firm up and say it in passing (likely mixed in with a few other questions so it doesn’t look like I’m concerned). If it comes down to the decision though, do you think it’s risky for me to go for the accounting apprenticeship when I don’t believe I’m going to get the grades or is it less important now I have the offer?