i also think that support centre would be where you have counsellors, where you run anxiety management classes or work on specific behaviours that need addressing.
if schools are expected to be doctors, psychologists, educators, nurses, etc then give them the facilities and the specialists to be all of that.
sure you could enforce a unit on sen onto teacher training but realistically it's still going to be superficial because it's such a broad area and no one professional be they teacher, doctor, whatever can know everything about everyone's condition. if schools now need to meet the needs of mentally ill children, physically disabled children, developmentally delayed children etc etc then put the professionals and the resources for dealing with those children in the school instead of pretending a teacher can be everything rolled into one for 25k a year.