I am attempting to filter e-mail on 1 account on my domain via message size.
I am new to Exim scripting and need to ensue this is correct before proceed.

Basically check is for support@mydomain and the size is less than 3mb then allow, if not less than 3mb block and send response to sender.

if $local_part_suffix is "support" and $message_size is above 3m then
mail
to $sender_address
from Support@mydomain.com
subject “RE: $h_subject:”
test “$sender_address , $h_subject: , $tod_ful \n\nYour message was over our 3MB size limit and was not processed please try truncating your message and send again.
seen finish
endif

Thank you for your assistance in advance.