The vendor the FBI contracted with to develop the exploit says they demonstrated it on March 20th. The FBI says they demonstrated on March 20th. In fact, they postponed a court hearing to attend the demonstration, and the following day informed the court. This is also 3 weeks after Comey's testimony to congress.
If you're going to throw out a conspiracy theory, you should have something to back it up.
If you're going to throw out a conspiracy theory, you should have something to back it up.