Who is responsible for sending offer letters?
Normal admissions round
Offers of primary and secondary places must be sent by the home local authority (LA) and schools must not contact parents about the outcome of their applications until after these offers have been received (paragraph 2.10 of the schools admissions code 2021).
This is true even if your LA isn't usually your admissions authority.
There is no requirement for LAs to co-ordinate in-year applications. Schools that are their own admissions authority can accept applications directly. In this case, schools must tell the LA about the application and its outcome.
Where a pupil is refused a place following an in-year application, the school must also inform parents about their right to appeal.
This is covered in paragraphs 2.23 to 2.31 of the school admissions code.
You can download a series of templates for in-year admissions letters from Kent County Council.