Spoiler alert! A disgruntled (and newly fired) employee from the Pretty Little Liars set took to Reddit on July 10th to answer any and all questions fans had. Below are spoilers for the rest of season six. I’ve tried to list them from least to most surprising so you can stop reading as you go along in order to save some surprises for later!
Leslie is not A. She was Bethany’s roommate in Radley. Her purpose in the show is to tell the girls that Cece was the one visiting Bethany and was pretending to be Alison.

Sara Harvey is not working with A, “She’s just a weirdo.” In fact, the liars find her sleeping in her old bed at the dollhouse. Emily finally decides that Sara is not psychologically stable
enough to be her girlfriend. (Honestly, Em. It took you that long?)

Maya is not alive. Nate/Lyndon killed her in season two. Charles knew she had found
baby pictures and other links to his existence in the house and threatened to kill her if she didn’t leave town. Lyndon just got to her first.

Lorenzo, Ali’s new beau, is going to die in an altercation with A.

A’s motives will be revealed. Over a couple episodes, we will learn Charles’ backstory and why he holds so much resentment toward the girls. We will also learn how Mrs. D faked his death and why she was killed.

“That night” Cece hit Bethany, Charles saw her and hit Ali thinking that she was Cece. Cece is not on the A team. She is afraid of Charles as much as anyone.

There actually is no A team. Charles is working alone. “Other people are doing their own things to protect their own secrets, so it might seem like it was A in the past, but it wasn’t. There’s no team, just A and other people being sketchy.” (What about all of those black hoodies at the playground in New York?)

Something really crazy, Spencer has met Charles multiple times. The first time was in Radley when she was a patient there as a child.

In the finale, the girls go to prom. “There is a bunch of drama over whether or not they can go...While the girls are at the dance, Ali is lured away by a message from Charles and he shows himself to her before the rest of the girls realize she’s gone." Ali will think she killed Charles before the body mysteriously disappears.

STOP READING NOW if you don’t want to know who A is.
Lastly, who is A/Charles? Are you ready?

It’s Wren. Yes, the dreamy British doctor isn’t so dreamy after all. He isn’t British either! He will eerily drop his accent mid-sentence when he reveals himself to Ali after the prom. (Not to brag, but I totally called it).

At the end of the finale, the girls will all receive a text simultaneously and look at each other in horror. Season Seven will have a new antagonist—Black Widow.
There is speculation about whether or not this is true. Producer I. Marlene King took to Instagram and posted this:

but soon after posted this:

The credibility is up in the air, but if you want to read the thread for yourself, you can find it here. Beware, there are even more spoilers on the thread than I gave you here.
We will have to wait until the season finale in August to find out for sure.
Tune into Pretty Little Liars on ABC Family Tuesday, August 11 at 8 to see the Big A reveal!