Another niggle:
If they have leave them free until everything is in place, in order to observe due process: does the strict timeline from arrest to trial apply to a tribunal or just to a civilian jury trial?
My limited understanding is that under the Patriot Act, bad actors can be swept up and held indefinitely until a military trial.
I'm sure the timelines are slightly different, but maybe by weeks, not by months or years.
There is no need to even PLACE an indictment in advance. Sometimes (usually) that happens AFTER the arrest. With more complex inditements, prepare over a period od weeks. File on day one and arrest on day one. Filing is a leak vector. There are crooked courts.