U1 - I was thinking this had to do with Uranium One.
Now, I’m pretty sure that it had to do with Carter Page. He was likely the UCE1 FBI undercover used to entrap a Russian spy. Spy pled guilty around 5/2016.
Then FBI took the info they had on Carter Page meeting with Russians in that case to convince the court that he was an actual spy-allowing them to get the warrant under Title 1. Just one more lie/perjury.
That allowed them to go back in time for CP and anyone else he might have seen even briefly. Thus covering their tracks to enable them to use anything they might have already collected illegally before the warrant.
Perpetually, on it’s face the application was absurd. Once exposed it’s outrageous - the judge(s) had to be in on it and would hope caught when given the opportunity.