In the original case the claimants argued that the different time limit constituted direct discrimination against foetuses on the grounds of disability - i.e. that foetuses had legal personhood and thus human rights.
Thankfully the judge threw out that argument because ECHR has never ruled that foetuses have personhood. We've seen how that reasoning works out in NI and some US states.
Of course a born baby has more rights - human rights begin at birth. Anything else leads to a very dark place for women, even those carrying much wanted pregnancies.
Even if you are staunchly anti-abortion, there is no need to make that argument - e.g. apart from a few exceptions, abortion past 24 weeks is illegal, nevertheless those foetuses do not have human rights under UK law.
The claimants were permitted to appeal on one ground - that having a different time limit for disabled foetuses stigmatises all disabled people by implying their lives are worth less, and therefore this is indirect discrimination against disabled people.
That's a fair argument. They will lose because this part of the Abortion Act is clearly a proportionate means of achieving a legitimate aim and therefore it's lawful. But I do understand why it's hurtful.
To me it seems obvious that the solution is to remove the 24 week time limit for all pregnancies. This is the law in Canada and as far as I know there are not hoards of women there demanding terminations during the final weeks of pregnancy, and there are not hoards of doctors lined up to do late abortions on an informed consent basis.