One quick trip to the Golden Oak Library and back later...
Rainbow snuck around the farm as she hid Applejack onto the roof of the Barn, so Twilight would not teleport her on sight again.
Once done, she set on locating Twilight. She was about to take off in a direction, when she heard a large *OH GOD THIS FUCKIN' HURTS, HOW DOES SHE DO THIS EVERY SINGLE DAY, HOLY SHIT* behind her.
Turning around, she saw Twilight getting on her hooves under a tree, bruised on everypart of her body.
Zooming to her, she started to shout: "OK, I'M BACK, YOU PURPLE FREA-", but Twilight's appearance gave her pause. "Uh, what happened to you?"
"What do ya mean? Ah'm just buckin' the trees like Ah' was earlier. Isn't that obvious?"
Before Rainbow could answer, she saw Twilight throw herself into a nearby tree, before falling down at its roots and slowly getting back up.
"So to buck apples, you just throw yourself into every tree one after the other?"
"Eyyup" explained Twilight.
"And that's it?"
"Eyyup" continued Twilight.
"...Huh, okay then, that actually makes sense. So I guess that really is what you were doing earlier... But ENOUGH ABOUT APPLES! I want to know what the fuck is up with you and AJ and I wanna know NOW!" she gently asked.
"Urgh, what's so fuckin' hard to get, for Faust's sake, Ah' was-"
"Wait, you know about that bitch too?" interrupted Pinkie Pie, peeping out from under Twilight's mane.
"...Uh, know about who?" questioned Twilight and Rainbow.
"Oh... nevermind.", Pinkie replied, slumping down in fury. "But I swear miss Faust, if I ever get my hooves on you, I'll make you sorry for making me an EARTH PONY YOU COLD HEARTED B-"
And just like that, she was removed from the show for the 5th time this month.
Shrugging the interruption, Twilight continued: "...so, as Ah' was about to yell calmly; Ah' was just bored of my excitin' life and Ah' wanted some excitement, so Ah' became Applejack because she has the most boring life Ah' know of, and made her take my place. Simple as that" she yelled calmly, as she claimed she would. She had kept her promise, surely that was very Applejacky, right?
Rainbow dash paused, processing the information, idly making some loop-de-loop and other occasional Sonic Rainbooms while thinking. Once she understood the situation, she took a deep breath and replied with the only possible logical reaction she knew: "Oh, I see; sorry for getting angry earlier, I didn't know, but that totally makes sense."
"That's okay, Ah' forgive you" Twilight whispered.
Suddenly, both of them were rudely interrupted agaik, this time by a huge scream of despair.
"...wwwwWWHAAAAAAT?!!!!"
Twilight and RD both slowly turned to the direction of the sudden sound, seemingly coming from the Barn, but seeing noone in it.
"*sigh* was that Twiligh', again?" Twilight herself said in an exasparated tone, her head rotation almost finished.
"Oh.. yeah, I kinda hid her on that roof so you wouldn't teleport her again, since I didn't know the situation. Sorry, I'll go get her", apologized Rainbow.
"Oh, Ah' see; please do, yeah" she nodded violently.
A rainbow trail later, Rainbow Dash was gone and back, this time having brought Applejack with her.
"Twilight," Rainbow firmly adressed Applejack, "AJ here told you to take her place, so do it, okay?"
"WHAT THE FUCKIN' KIND OF GAY FLYIN' FUCK DO YOU THINK YOU ARE, RAINBOW? AH' HEARD WHAT THAT DUMB BITCH SAID, HOW ARE YOU AGREEING WITH HER??" Applejack refused.
"Well you see, I heard what she said too" chirped Rainbow, "and I'm surprised and annoyed you're still here after that. She explained me everything, and I'm sorry AJ, but she's right, you have to stay at the Golden Oak Library, now", she gently shouted to the earth pony next to her.
"Wha-?! Ah' fuckin' swear to Fau- uuuh, Ah' mean Celestia, Rainbow; you better be fuckin' joking here, or you ain't gonna be flying outta this straight!" She rudely threatened.
"*sigh*, Whatever" Rainbow said, truly annoyed. "Can you just get her there again, AJ? She's gotta tire out from making the trip at some point."
"Yeah, you're righ' ", agreed Twilight. She started lighting her horn again.
"A-" Applejack started, but before she could finish her sentence, she got teleported again in the Golden Oak Library.
"...Ah'm just gonna pass out from the uncomprehesion and puzzlement, and then, we'll see how they like to spit their nonsense at the fuckin' princess. This ain't over yet." screamed AJ at the top of her lungs before instantly collapsing on the ground, ready to end this whole nonsense when she'd wake up, one way or another.