Enforced inbound TLS ciphers

[lists]

I'm enforcing inbound TLS from my internal network with these settings:
main.cf
  smtpd_tls_security_level = may

  smtpd_sender_restrictions =
   check_client_access cidr:/etc/postfix/enforced_inbound_tls.cidr

enforced_inbound_tls.cidr
  10.0.0.0/8      reject_plaintext_session

My question is, does the following setting in main.cf apply to tls 
connections that are enforced with check_client_access? If yes, then is 
there a way to set this to low for a particular IP or subnet, and leave 
it to medium for everybody else?

smtpd_tls_mandatory_ciphers = low