Okay, so there are a hell of a lot of theories that say that Andrew is Charles/A/whatever we’re calling them these days. While I really don’t (or don’t want to) believe this due to his relatively fluctuant appearances in the show and how painfully obviously shady the writers have been making him look recently, I do however think that he may in fact be Varjak, but not for the reasons the Liars think.
So now onto how Sara Harvey ties into all of this and most importantly Varjak’s phone number that the girls found. I’m sure you’ve all seen or heard about the phone number decoding to spell out SARA HARVEY and to me, this seems to be the biggest clue to Varjak being to do with Sara as opposed to A or Alison. A lot of hotlines often use the method of having their telephone numbers spell out certain phrases as a means for the public to remember them and I’m starting to think that this is exactly what Varjak is up to. He’s looking into Sara’s death/disappearance just like the liars have been constantly doing for the entire show over Ali’s disappearance and we all know how ridiculously suspicious they’ve made themselves look over time. Marlene did say that we would eventually find out what happened to Sara, and this again adds to my belief that Varjak is actually investigating what happened to Sara and not Ali and this also suggests that there is in fact a link between what happened to Ali and Sara.
Now obviously I haven’t covered WHY Andrew would be looking into Sara’s disappearance, or how he knew her, and that’s largely because right now I don’t know why. But I do think that his shady and very red herring style behaviour does mean something, he’s not A, but he could be Varjak.