A National Audit Office report out today (Guardian report here) questions whether free schools are value for money and, worse, whether they are having a negative impact on existing schools in terms of squeezed capital costs and the creation of surplus capacity which makes other schools uneconomic.
For example, nearly 50% of the 113,500 new places opened in mainstream free schools since 2015 would create spare capacity in other nearby schools, 'potentially affecting their future funding', and for each new free school opened in 2015, five existing schools would feel a moderate to high impact on their funding.
Incidentally, it must be much harder to predict pupil population trends with Brexit since we don't know yet what rights EU citizens will have or how many people decide to leave the country anyway. But I noticed Tania Mathias was one of only three Conservative MPs to vote for the Brexit bill amendment guaranteeing their rights.