I was given a referral link on 4/28 and uploaded my resume to Delta's website. On 5/2 I was sent a request to fill out an application invitation. Pretty standard stuff, nothing out of the ordinary. On 5/5 I was sent an email from HireVue to record a digital interview which I did. I wore a white shirt and tie for the interview, you only get one chance to record your response to the questions so make sure and do some practice questions before hand.
Everywhere I read said that they heard back within 2 weeks if they were asked to come in for a face to face interview. Delta was going through some major changes at LAX (where I was applying for) at the time of my digital interview, but it's been almost 6 weeks and I haven't heard anything back. I'll apply again if the position comes up, but I haven't heard anything yet and there's no contact info regarding a hiring manager for me to follow up with. I even asked my cousin, who sent the referral link, and he couldn't find out who it was for me to call. Every where I read and everyone I talk to says Delta's the airline to work for in the industry so I'll keep at it.