The figure comes from a summer poll of LAs and chains asking if they thought schools would be ready to provide hot meals in September. LAs guesstimated the majority would be yes, though I am unsure if this can be translated into facts on the ground.
I know a number of schools who planed to have hot meals, but due to a variety of issues are actually providing cold meals. I would also question of the LAs know exactly what is happening in school kitchens.

The issue laws ignores ifs the cost of getting there. Both in financial terms and in time effort and stress on school leaders.

What damage has implementing this policy done to school finances, to LA budgets?
What level of disruption are schools enduring?

Many schools will be fine, but some will have issues, but Laws ignores them pretending it is all gone fantastically.

No one doubted that school leaders could implement the policy (more or less) the issue has always been at what cost. That point remains as valid as it ever was.