Criminal cases tend to progress much more quickly in federal court than in state court. In general, the majority of federal cases tend to reach conclusion within 6 to 12 months of arrest and indictment. However, there are exceptions for large conspiracy and financial type cases. Some very large federal cases can have 25, 50, or more defendants. When there are that many people fighting the same case it can take extra time.
The Speedy Trial Act requires that an indictment must be sought within thirty days of a person's arrest. Additionally, if an indictment has already been returned and the defendant is in jail, the Speedy Trial Act requires the government to be ready to proceed to trial in 70 days. If the government is not ready to proceed to trial in the required amount of time, that can give rise to the defendant having additional rights as to being temporarily released from jail. All federal prosecutors and agencies are aware of these rules and usually do not move forward prosecuting a case until they have all the evidence that they can gather to be ready for trial.
It is not uncommon for a defendant in a federal case to waive the right to have a trial in that short of amount of time in order to hire an attorney and give them enough time to investigate the allegations before proceeding to trial.