If you notice the FBI list
1-99 covers most domestic crimes like
3 - Overthrow or Destruction of the Government
7 - Kidnapping
9 - Extortion
15 - Theft from Interstate Shipment
17 - Fraud Against the Government — Veterans Administration
29 - Bank Fraud and Embezzlement
31 - White Slave Traffic Act
36 - Mail Fraud
37 - False Claim Against the Government
45 - Crimes of the High Seas
46 - Fraud Against the Government - Renegotiation Act - Civil Suits; False Claims - Civil Suits
50 - Involuntary Servitude and Slavery
52 - Government Property - Theft, Robbery, Embezzlement, Illegal Possession, Destruction
54 - Customs Laws and Smuggling
61 - Treason
62 - Administrative Inquiries (Miscellaneous Subversive and Non-Subversive)
63 - Miscellaneous Non-Subversive
64 - Foreign Miscellaneous
65 - Espionage
67 - Bureau Applicant Matters
72 - Obstruction of Justice
74 - Perjury
81 - Gold Hoarding
87 - Interstate Transportation of Stolen Property
88 - Unlawful Flight to Avoid Prosecution
89 - Assaulting, Killing or Attempting to Kill a Federal Officer, etc
98 - Sabotage
The higher numbers mostly deal with foreign issues
I must believe Q is pointing to crimes that occured that fall in the first 99 crimes listed
https://www.archives.gov/research/investigations/fbi/classifications
81 - Gold Hoarding
LOL! Is that a crime now? Who knew!
So maybe Q CLAS 1-99 might indicate a period of martial law when mass arrests are executed?