Why do emails from ithelp@uoguelph.ca say "When replying, type your text above this line"?

When someone replies to messages originating from the service desk email address ithelp@uoguelph.ca, the information in their reply gets added to the record for that support request.  Because the replies will often contain a lengthy thread of sequential replies, the service desk application needs a flag that tells the email processor, “once you get to this point of the email, the rest of the email is already recorded in previous updates”.  The flag that is used to detect this point in the message is the phrase “When replying, type your text above this line”.  This also avoids potential issues where people will highlight content or add content by editing parts of the email reply thread.  Our service desk application and the IT Help Centre agents would miss those changes because they are made “below the line”.