Oddsocks NEC (National Extension College) is a charity linked with the Open University which does distance learning A levels. They organise everything I think. Google.It costs abotu 450 per Alevel. Avoid something called OS (Op..S..u..y) they seems to be a con with thousands of fake reviews.
Or your dd could do an private IGSE in Biology at higher level (maybe IGSe are already higher level - I'm not sure) and then get onto a state funded A level Biology course.
there are so many options, particularily as stage 4 education is funded up to 19, so taking three years to achieve A levels is free, whether by means of retakes, or other changes.
Like second my son changed his A levels in Year 12, although for him unfortunately one changed as late as end of Year 12. Ds1's school started them on 4 which was a big mistake for him, although other students I know liked the range and the choice. 3 A levels mean you can really get your teeth into them from the beginning and by half term you can change if one is unbearably "wrong" for student.
I think the commonest situation is to find that sciencey student really hates writing essays, or vice versa that an humanities student really finds Stem subjects much more boring than they thought they would, despite achieving excellent GSCE grades in a subject like Maths or Chemistry.
The other big mistake is not to undertake any preliminary reading on the syllabus before you start the syllabus, in the holidays; I think then you can judge how interesting it really is. A few projects or reading lists before hand would make so much difference. Ds1's school did not offer or suggest this, but ds2's school makes a condition of starting the A levels. You hit the ground running then.