Port 465 is used for SMTP and this is supposedly deprecated for secure email. However, using TLS from the start of the communications seems far more secure than starting off with insecure communications and then trying to upgrade it with a command to begin TLS, as happens with STARTTLS. There are possible attacks against STARTTLS in which the command to begin secure communications is removed or overwritten which could then result in email being transferred in plain text over the internet and be readable by third parties.
+ ++From http://motherboard.vice.com/read/email-encryption-is-broken: +
+ +++The researchers also uncovered mass scale attacks of STARTTLS sessions being stripped of their encryption. That attack itself isn't new: internet service providers sometimes do it to monitor users; organizations may use it to keep an eye on employees; or it may come from a malicious actor +
+