Hi all,
Unfortunately, as you probably expect, there is not yes or no answer to this. I remember being in the same position as you all 4 years ago asking the same thing.
In general, this will depend on 2 things.
The first being if your offer contains grade specific expectations, eg. need an A* in maths. I know at least for maths, if you don't get A*s in maths and further, it's almost impossible to be given a place without any mitigating circumstances.
The second is how many people meet their offer this year, which is why this question becomes difficult to answer.
Whilst there is no guarantee for any subject or any grades except your offer, I did maths as my undergrad at Warwick and got A*A*AB, with the B being in English Literature and I was still given a place. Even then, this was likely due to it being in English and also my background of state school/ living in an area where very few people go to University may have also contributed to this, I will never know.
So it is possible in certain cases, however, I would also try to remind yourself to take comfort in the fact that the grade boundaries are there for a reason. Whilst I did get onto the maths course, I found it very hard and would probably have suited the Maths/Physics course more, which is what a lot of people who missed their grades were offered instead.
So in some ways, it may mean you end up on a course that's more suited to you.
Overall, try not to worry about it, I understand that's easier said than done, and any other questions about this process or about Warwick in general, feel free to ask!
Hope this helps.
Davina