Pr00ne, I am not so sure.
I was at a village church this morning. It was standing room only. Cubs, guides, cadets at the front, all ages, besides the organizations from teens upwards.
Some where 'incorrectly dressed' others dressed formally.
Nige321, it is not a come as you are event, dressing formally shows care and respect. Admittedly, better to be there than not there at all.