VirtualBox - can't telnet to SMTPS service on guest machine

Question

I have Debian7 running VirtualBox v4.1.18, with a guest VM running CentOS 7 which runs Dovecot. I'm able to telnet to 995 from localhost (i.e., from the VM to itself) and other guest machines, and I can do basic auth using simple commands, but I cannot telnet from the host to the guest machine. Here is the output of

firewall-cmd --list-all

  public (default, active)
  interfaces: eth0 eth1
  sources: 
  services: dhcpv6-client imaps pop3s smtp ssh
  ports: 465/tcp 587/tcp 995/tcp
  masquerade: no
  forward-ports: 
  icmp-blocks: 
  rich rules:

I also have 995 forwarded on my VirtualBox manager for this host. I can ssh into the box just fine... I can hit port 465/587... I have verified my host machine is not consuming 995... I have restarted the VM and the host machine multiple times....

Here is my dovecot.conf:

fs
auth_mechanisms = plain login
disable_plaintext_auth = no
listen = *
mail_location = maildir:/var/mail%d/%n
mail_privileged_group = mail
mbox_write_locks = fcntl
namespace inbox {
  inbox = yes
  location =
  mailbox Drafts {
    special_use = \Drafts
  }
  mailbox Junk {
    special_use = \Junk
  }
  mailbox Sent {
    special_use = \Sent
  }
  mailbox "Sent Messages" {
    special_use = \Sent
  }
  mailbox Trash {
    special_use = \Trash
  }
  prefix =
}
passdb {
  driver = pam
}
protocols = pop3
service auth {
  unix_listener /var/spool/postfix/private/auth {
    group = postfix
    mode = 0660
    user = postfix
  }
}
ssl = required
ssl_cert = </etc/pki/dovecot/certs/dovecot.pem
ssl_key = </etc/pki/dovecot/private/dovecot.pem
userdb {
  driver = passwd
}

What can I to to fix this or diagnose it further?

edit:

After a restart, I have changed the host port from 995 to some other port and was able to successfully telnet to the dovecot service. I might have something on Debian7 blocking 995? Not sure...