There's an election coming up.
Oh yes, it's a carrot/stick moment!
Further reading has told me that in our situation (with a 10 month old), we would get 15 hours in September 2024 and only qualify for the full 30 hours in 2025, by which time he would be 3 years old and would be eligible anyway under the current system. So - as ever - the headline telling everybody that working families are to get 30 hours' free childcare isn't exactly true, as many won't benefit from the change at all.
It needs to be introduced ASAP.