I actually took the flashback extra reveals to mean the revealing of new storylines stemming from the same night as the shooting. If the father-of-the-baby reveal happened that night you'd already be seeing the fallout of that. I'm guessing the Paddy secrecy will be one of those reveals, at the very least, as well as revealing who the shooter is. Whatever the other revelation is had to be tied in with whatever else happened that night, and may have something to do with why there are shady looks between certain characters that up til now seemed to be just about the shooting and "who dunnit". And with Kate saying they lead into the winter viewing also makes it seem like new(ish) storyline threads.
Here is the recap for the night of the shooting - could there possibly be clues within? Such as...what was Andy's call really about - the shooting, or something else?
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Airs Friday, Sep 25 2015 at 19:00 BST on ITV
Andy flies at Robert as he is sickened by his manipulation. Aaron breaks the fight up, but Andy is shocked further when Chas guiltily covers for Aaron and Robert - lying that Katie was going to leave him. Andy runs out when Diane and Victoria start to be hoodwinked by Robert's lies. Chas privately tells Robert to drop dead when he thanks her.
Robert's troubles continue when Lawrence confronts him, explaining that he had an interesting chat with Chrissie. Steeling himself for a fight, Robert explains about the break-in and gloats that he set up the rent boy. Lawrence is infuriated.
Later that day, Chas warns Robert to leave the village tonight if he values his life. However, Robert doesn't take notice of Chas's warning. As he takes a step back, there's a sudden sound of a gunshot. Blood appears on Robert's chest. His eyes meet Chas's in utter shock as he collapses...
Meanwhile, Diane receives a call from Andy who apologises, but adds that if she'd heard what Robert did to Katie she'd do the same thing. He hangs up, leaving Diane and Victoria extremely worried.
Elsewhere, Debbie tells a disappointed Ross that she can't give him what he wants. Pete watches triumphantly as his brother feels the pain of rejection. Ross is fuming that Pete saw Debbie rejecting him and Pete tries to cover a twinge of worry as a murderous Ross explains that Debbie was the only thing stopping him from using the gun. Pete regrets rubbing Ross's nose in it when he gets a text to meet him at the farm. Moira is floored when he says that Ross will be waiting with a gun. She tells Pete they'll meet him together.
Also, Harriet is worried when Ashley doesn't show for her party.
Finally, Marlon gets on well with Chloe at the singles night, but Paddy is worried about Aaron and makes his excuses to leave.
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Of course, I could be completely wrong, as I'm only guessing based on the spoilers and comments given on this forum, as well as the memes on the Emmerdale FB page (character facial expressions/reactions etc), and photos on Digital Spy etc, since here in NZ we are several weeks behind and falling further behind thanks to TVNZ cutting our viewing time of Emmerdale in half since the beginning of September (don't get me started on that!)