The Lord is "The Devil Herself". The Last Seraphim is Betweenford. Oric killed all the other Seraphims, and allowed Ford to live, the weakest of the Seraphim (I know he's the most powerful angel bear with me). So Oric devises this whole system of cycles and producing energy, yadayada we all read Cain's story. But he basically allows Ford free will as long as he follows orders.
So Ford starts resurrecting the Seraphim. But like the Target, they lack most of their power and memories from their previous incarnations, making Ford more powerful than any of them. Two of whom we've met, and a third who we saw in that Angel flash. They no longer have the title of Seraphim, as they don't have the power behind them to maintain that title. So they are Angels.
Oric starts to catch on. He realizes that Betweenford is up to something bringing these Angel helper minions into the Warrens. When Oric gets word of the new recruit from Spira (On DL3, where we found him keeping shop), he knows for sure that something's up. He knows there's only so many Seraphim, and already suspects that the Angels are resurrected Seraphim. There's only a matter of time before their leader, "The Devil Herself" according to Cain, is resurrected. Little does he know it already happened, and she's back to full strength already. Their Lord doesn't need Betweenford to resurrect and train the Seraphim anymore, bye bye weakest of the bunch, you can go back to being the weakest one; maybe you'll die, and when we resurrect you, you'll be weakened like us, too, and the old pecking order will be restored.
So the Lord is back to full strength (TRAINING'S OVER), doesn't need her tool to ascension anymore (BYE BYE OLD FORD), is about to take down Oric (DOWN WITH THE KING), and is the ruler of the Angels (LONG LIVE THE LORD).
I need to go back and find the relevant quotes to finalize this.