Not sure where your info is from… grandjuries are assembled- ergo Dissolved too
https://www.nolo.com/legal…/why-prosecutors-choose-grand-juries-preliminary.html
Unlike a preliminary hearing, held in court with the defense side present, the grand jury does not make its decision in the context of an adversary proceeding.
grandjuryresistance.org/grandjuries.html
Unlike the "petit" jury, which is used to determine guilt in a trial, a grand jury consists of 16 to 23 jurors who are not screened for bias. The purpose of the grand jury is not to determine guilt or innocence, but to decide whether there is probable cause to prosecute someone for a felony crime